feat(teams): the slash-command seam, and the first command through it

Phase 7 of TEAMS.md. `api.registerSlashCommands` stops throwing: a module
registers a command's DEFINITION and its HANDLER together, the bot pulls the
definitions over the internal listener and runs none of our code, and the
handler executes here — forced by the bot container having no `modules` volume,
and the right boundary anyway.

Registration validates what Discord would reject as a batch (names, description
lengths, the four option types, required-before-optional), because the bot
registers the whole set in one PUT and a single bad entry costs every command
including the bot's own. Commands are not namespaced under their owner — there
is no dot in Discord's name grammar — so collisions are first-come with the
holder named.

The dispatcher is the access boundary: `linked` has no Discord equivalent, so
the platform-side permission default can only ever be advertising. It resolves
the actor by `auth_providers.kind` rather than the id slug, treats a banned
account as unlinked, bounds a handler under the bot's own timeout, and keeps
`ok` outside the envelope so a handler cannot forge it.

Liveness is asked at both the pull and the dispatch. The registries have no
removal path, so a module an operator disables at runtime would otherwise keep
a live handler behind a command Discord still advertises.

Co-Authored-By: Claude <noreply@anthropic.com>

bot/test/appInternalClient.test.js

@@ -0,0 +1,77 @@
+// The bot→app internal client (TEAMS.md §7.1).
+//
+// One property carries this file: the base URL is DERIVED from
+// `SITE_INTERNAL_URL`, which already names the app's internal listener with a
+// path on the end. That derivation is the reason every existing deployment gains
+// slash commands with no compose change, and it is exactly the kind of string
+// handling that breaks silently — a wrong base means "the app is down" forever,
+// with nothing in the logs but a fetch error.
+
+const { test, beforeEach, afterEach } = require('node:test')
+const assert = require('node:assert/strict')
+
+const env = { ...process.env }
+const realFetch = global.fetch
+
+beforeEach(() => {
+  process.env.SITE_INTERNAL_URL = 'http://app:3001/internal/bot-config'
+  process.env.BOT_INTERNAL_KEY = 'shh'
+  delete require.cache[require.resolve('../src/site/appInternalClient')]
+})
+
+afterEach(() => {
+  process.env = { ...env }
+  global.fetch = realFetch
+})
+
+/** Load the client fresh and record the single fetch it makes. */
+function withFetch(response) {
+  const seen = {}
+  global.fetch = async (url, init) => {
+    seen.url = url
+    seen.init = init
+    return response
+  }
+  // eslint-disable-next-line global-require
+  return { client: require('../src/site/appInternalClient'), seen }
+}
+
+const ok = (body) => ({ ok: true, status: 200, json: async () => body })
+
+test('the commands URL is the internal listener’s origin, not its bot-config path', async () => {
+  const { client, seen } = withFetch(ok({ version: 3, commands: [] }))
+  const res = await client.fetchCommands()
+  assert.equal(seen.url, 'http://app:3001/internal/commands')
+  assert.equal(seen.init.headers['X-Internal-Key'], 'shh')
+  assert.deepEqual(res.data, { version: 3, commands: [] })
+})
+
+test('a dispatch names the platform, so the app never has to guess', async () => {
+  const { client, seen } = withFetch(ok({ ok: true, response: {} }))
+  await client.dispatchCommand({ command: 'guild', options: { name: 'KOC' }, platformUserId: '5', guildId: '9' })
+  assert.equal(seen.url, 'http://app:3001/internal/commands/dispatch')
+  assert.deepEqual(JSON.parse(seen.init.body), {
+    command: 'guild', options: { name: 'KOC' }, platform: 'discord', platformUserId: '5', guildId: '9',
+  })
+})
+
+// A bot with no internal URL configured is an ordinary deployment state (the
+// warning already exists in bootstrap.js); it must not become an exception on
+// every `ready`.
+test('an unconfigured or unparseable SITE_INTERNAL_URL is a refusal, not a throw', async () => {
+  delete process.env.SITE_INTERNAL_URL
+  const { client } = withFetch(ok({}))
+  assert.equal((await client.fetchCommands()).ok, false)
+
+  delete require.cache[require.resolve('../src/site/appInternalClient')]
+  process.env.SITE_INTERNAL_URL = 'not a url'
+  // eslint-disable-next-line global-require
+  assert.equal((await require('../src/site/appInternalClient').fetchCommands()).ok, false)
+})
+
+test('a non-2xx carries its status so the caller can tell "down" from "rejected"', async () => {
+  const { client } = withFetch({ ok: false, status: 401, json: async () => ({}) })
+  const res = await client.fetchCommands()
+  assert.equal(res.ok, false)
+  assert.equal(res.status, 401)
+})

bot/test/dynamicCommands.test.js

@@ -0,0 +1,225 @@
+// ── The bot's half of module slash commands (TEAMS.md §7.1) ────────────────
+//
+// The first tests in this package, and they exist for a specific reason: phases
+// 8 and 9 put more of the Discord integration in this process, and the failure
+// modes here are ones no unit test in `server/` can see — a whole-set PUT that
+// one bad entry poisons, a deferral that has to happen before anything slow, and
+// a reply that must be EDITED rather than sent once the interaction is deferred.
+//
+// Nothing here talks to Discord. `interaction` is a fake that records what was
+// called on it, which is the whole of what this file is asserting about.
+
+const { test, beforeEach } = require('node:test')
+const assert = require('node:assert/strict')
+
+const dynamic = require('../src/discord/dynamicCommands')
+const appInternal = require('../src/site/appInternalClient')
+const staticCommands = require('../src/discord/commands')
+
+const originals = {
+  fetchCommands: appInternal.fetchCommands,
+  dispatchCommand: appInternal.dispatchCommand,
+  get: staticCommands.get,
+}
+
+beforeEach(() => {
+  dynamic._reset()
+  Object.assign(appInternal, originals)
+  staticCommands.get = originals.get
+})
+
+const definition = (over = {}) => ({
+  name: 'guild',
+  description: 'Show a guild',
+  owner: 'uo',
+  access: 'everyone',
+  options: [{ name: 'name', type: 'string', description: 'Guild name', required: false }],
+  ...over,
+})
+
+const answers = (commands, version = 1) => {
+  appInternal.fetchCommands = async () => ({ ok: true, data: { version, commands } })
+}
+
+function fakeInteraction({ commandName = 'guild', options = {}, userId = '555' } = {}) {
+  const calls = []
+  return {
+    calls,
+    commandName,
+    guildId: '999',
+    user: { id: userId },
+    options: {
+      get: (name) => (name in options ? { value: options[name] } : null),
+    },
+    deferReply: async (payload) => calls.push(['defer', payload]),
+    editReply: async (payload) => calls.push(['edit', payload]),
+    followUp: async (payload) => calls.push(['followUp', payload]),
+  }
+}
+
+// ── Pulling ────────────────────────────────────────────────────────────────
+
+test('a pull reports whether the set moved, so a nudge is cheap', async () => {
+  answers([definition()], 7)
+  assert.deepEqual(await dynamic.pull(), { ok: true, changed: true, count: 1 })
+  // Same version, same size: nothing to re-register, and re-registering anyway
+  // would mean a REST.put per module state change instead of per real change.
+  assert.deepEqual(await dynamic.pull(), { ok: true, changed: false, count: 1 })
+  answers([definition()], 8)
+  assert.equal((await dynamic.pull()).changed, true)
+})
+
+// Otherwise a restart blip would deregister every module command from Discord
+// and re-register it a minute later, with members watching it happen.
+test('a failed pull keeps the set already registered', async () => {
+  answers([definition()])
+  await dynamic.pull()
+  appInternal.fetchCommands = async () => ({ ok: false, error: 'ECONNREFUSED' })
+  assert.deepEqual(await dynamic.pull(), { ok: false, changed: false, count: 1 })
+  assert.equal(dynamic.definitions().length, 1)
+})
+
+// The collision the app cannot see: it validates against what IT registered and
+// does not know the bot's own array exists. Two entries of one name in a single
+// PUT is rejected as a batch, taking the built-ins down with it.
+test('a module command that collides with a built-in is dropped, not registered', async () => {
+  staticCommands.get = (name) => (name === 'ping' ? { data: { name: 'ping' } } : undefined)
+  answers([definition({ name: 'ping' }), definition()])
+  await dynamic.pull()
+  assert.deepEqual(dynamic.definitions().map((d) => d.name), ['guild'])
+  assert.equal(dynamic.has('ping'), false)
+})
+
+test('definitions carry Discord’s numeric option types, not the contract’s names', async () => {
+  answers([definition({
+    options: [
+      { name: 'who', type: 'user', description: 'A member', required: true },
+      { name: 'n', type: 'integer', description: 'How many', choices: [{ name: 'one', value: 1 }] },
+    ],
+  })])
+  await dynamic.pull()
+  const [data] = dynamic.definitions()
+  assert.deepEqual(data.options.map((o) => o.type), [6, 4])
+  assert.deepEqual(data.options[1].choices, [{ name: 'one', value: 1 }])
+  assert.equal(data.default_member_permissions, undefined)
+})
+
+// `linked` has no Discord equivalent — there is no "has a website account"
+// predicate — so only `staff` maps, and the app re-checks both regardless.
+test('only access: staff becomes a Discord permission default', async () => {
+  answers([definition({ access: 'staff' }), definition({ name: 'other', access: 'linked' })])
+  await dynamic.pull()
+  const [staff, linked] = dynamic.definitions()
+  assert.equal(typeof staff.default_member_permissions, 'string')
+  assert.equal(linked.default_member_permissions, undefined)
+})
+
+// ── Executing ──────────────────────────────────────────────────────────────
+
+test('the deferral happens before the dispatch, always', async () => {
+  answers([definition()])
+  await dynamic.pull()
+  let deferredFirst = false
+  const interaction = fakeInteraction()
+  appInternal.dispatchCommand = async () => {
+    deferredFirst = interaction.calls.length === 1 && interaction.calls[0][0] === 'defer'
+    return { ok: true, data: { ok: true, response: { text: 'hi' } } }
+  }
+  await dynamic.execute(interaction)
+  assert.ok(deferredFirst, 'the website is never in Discord’s 3-second ack path')
+  assert.deepEqual(interaction.calls.at(-1), ['edit', { content: 'hi' }])
+})
+
+test('the options the member supplied are passed by name, as plain values', async () => {
+  answers([definition({
+    options: [
+      { name: 'name', type: 'string', description: 'd' },
+      { name: 'who', type: 'user', description: 'd' },
+      { name: 'missing', type: 'string', description: 'd' },
+    ],
+  })])
+  await dynamic.pull()
+  let sent = null
+  appInternal.dispatchCommand = async (body) => {
+    sent = body
+    return { ok: true, data: { ok: true, response: {} } }
+  }
+  await dynamic.execute(fakeInteraction({ options: { name: 'KOC', who: '42' } }))
+  assert.deepEqual(sent.options, { name: 'KOC', who: '42' })
+  assert.equal(sent.platformUserId, '555')
+  assert.equal(sent.guildId, '999')
+})
+
+test('a title or fields render as an embed; a bare text does not', async () => {
+  answers([definition()])
+  await dynamic.pull()
+  appInternal.dispatchCommand = async () => ({
+    ok: true,
+    data: { ok: true, response: { title: 'Knights', text: 'Alliance: Accord', fields: [{ name: 'Members', value: '12' }], url: 'https://site.test/uo/guilds/7' } },
+  })
+  const interaction = fakeInteraction()
+  await dynamic.execute(interaction)
+  const [, payload] = interaction.calls.at(-1)
+  assert.equal(payload.embeds[0].title, 'Knights')
+  assert.equal(payload.embeds[0].description, 'Alliance: Accord')
+  assert.equal(payload.embeds[0].url, 'https://site.test/uo/guilds/7')
+})
+
+// §9 answer 5: the public projection, plus a private nudge to link. One reply
+// cannot be both, so the aside is a follow-up — which is the bot's decision to
+// make, not the handler's.
+test('a notice becomes an ephemeral follow-up beside a public answer', async () => {
+  answers([definition()])
+  await dynamic.pull()
+  appInternal.dispatchCommand = async () => ({
+    ok: true,
+    data: { ok: true, response: { text: 'public', notice: 'Link your account' } },
+  })
+  const interaction = fakeInteraction()
+  await dynamic.execute(interaction)
+  assert.deepEqual(interaction.calls.at(-1), ['followUp', { content: 'Link your account', ephemeral: true }])
+})
+
+test('a notice is not repeated when the answer was already private', async () => {
+  answers([definition({ access: 'linked' })])
+  await dynamic.pull()
+  appInternal.dispatchCommand = async () => ({
+    ok: true,
+    data: { ok: true, response: { text: 'private', notice: 'Link your account' } },
+  })
+  const interaction = fakeInteraction()
+  await dynamic.execute(interaction)
+  assert.deepEqual(interaction.calls[0], ['defer', { ephemeral: true }])
+  assert.equal(interaction.calls.some(([kind]) => kind === 'followUp'), false)
+})
+
+// Every failure path EDITS. Replying to a deferred interaction throws, so a
+// refusal that used reply() would turn a clean "no" into an unhandled error.
+test('a refusal is phrased by the bot and edited into the deferred reply', async () => {
+  answers([definition({ access: 'linked' })])
+  await dynamic.pull()
+  appInternal.dispatchCommand = async () => ({
+    ok: true, data: { ok: false, reason: 'forbidden', access: 'linked', isLinked: false },
+  })
+  const interaction = fakeInteraction()
+  await dynamic.execute(interaction)
+  assert.match(interaction.calls.at(-1)[1].content, /Link your Discord account/)
+  assert.equal(interaction.calls.filter(([kind]) => kind === 'edit').length, 1)
+})
+
+test('an unreachable app is the same sentence to the member and a different line in the log', async () => {
+  answers([definition()])
+  await dynamic.pull()
+  appInternal.dispatchCommand = async () => ({ ok: false, error: 'timeout' })
+  const interaction = fakeInteraction()
+  await dynamic.execute(interaction)
+  assert.match(interaction.calls.at(-1)[1].content, /Something went wrong/)
+})
+
+test('an interaction for a command the app no longer serves is left alone', async () => {
+  answers([definition()])
+  await dynamic.pull()
+  const interaction = fakeInteraction({ commandName: 'gone' })
+  assert.equal(await dynamic.execute(interaction), false)
+  assert.deepEqual(interaction.calls, [], 'nothing is deferred for a command that is not ours')
+})