refactor(client): delete the UO client half (phase 3, slice 3)

35 files and 5,332 lines out — twelve public pages, seven admin views, two
player views, eight components, the two `data/` leaves and the three `lib/`
ones, plus the two tests that came with them. §2.7.1's estimate of 51 files /
~3,700 lines was measured differently and is corrected in the docs PR.

The seams core keeps, each smaller than what it replaced:

Nine rows leave the public header and six leave the admin sidebar, and both
lists are now free of `feature` gates and of `IconShard`. `moduleTitle` already
handled a module page's heading, so the six TITLES entries and the
`/admin/characters` branch of `sectionTitle` simply go.

`/player` had `PlayerCharacters` as its index — a UO page — and rather than name
a replacement or invent a landing screen it now resolves to the first row of the
portal nav this viewer can reach (`firstDestinationFor`, beside
`allowedPathsFor` and reading the BASE nav for the same reason: an override is
presentation and where everybody lands is behaviour). With the module installed
that is still Characters, so a player's first screen after signing in does not
change. Deliberately generic and deliberately not in the portal layout — the
admin index is the same question with a hardcoded answer, and if the two
logged-in areas ever become one this is what serves both.

`game_account_signup` goes with the rest of core's UO prose: the mode list, the
derived public flag, the validation and a Site Settings field whose help text
named Bridge.cfg. The row itself is untouched and module-uo reads it through
ctx.settings — the data stays, the semantics move.

KNOWN BREAK, accepted by the org lead: the shipped Android app reads
`gameAccountSignup` off `/public/settings` (PublicDto.kt:80). The field has a
`= false` default so nothing crashes; the app silently stops offering
game-account creation until it reads the module's `/public/shard/features`
instead. Out of scope here, recorded in the Android plan, and it lands well
before this workstream's cutover reaches `main`.

620 server + 161 client tests. Manifest 158 public + 2 internal, unchanged;
routes.guards unchanged. The OpenAPI spec loses exactly one property, and only
because it was hand-written in swagger.js — regeneration alone would have left
the spec documenting a field core no longer returns.

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

server/test/settingsGameSignup.test.js

@@ -0,0 +1,75 @@
+// ── What core's settings no longer know about ──────────────────────────────
+//
+// Phase 3, slice 3. `game_account_signup` policy left core: the mode list, the
+// derived public flag, the validation and the Site Settings field. The row in
+// the `settings` table is untouched and module-uo reads it through
+// `ctx.settings`, which is the whole point — the DATA stays, the SEMANTICS move.
+//
+// This file exists because the deletion passed 616 tests without one of them
+// noticing. Nothing asserted the shape of `getPublic()`, so a field could leave
+// the public settings payload — which the SPA, the Android app and the Discord
+// bot all read — and no suite would say a word. That is worth a test in the
+// direction of "and it is gone", but it is much more worth one in the direction
+// of "and nothing else went with it".
+
+process.env.DB_HOST = '127.0.0.1'
+process.env.DB_PORT = '59999'
+
+const { test, after, afterEach } = require('node:test')
+const assert = require('node:assert/strict')
+
+const settings = require('../src/model/settings/settings.model')
+const settingsDb = require('../src/model/settings/settings.db')
+const db = require('../src/utils/db')
+
+after(() => db.close())
+
+const originals = { getAll: settingsDb.getAll, get: settingsDb.get }
+afterEach(() => Object.assign(settingsDb, originals))
+
+// Both readers, because the two halves of this test read different ones:
+// `getPublic` folds `getAll`, and a module's `ctx.settings.get` is `get`.
+const withRows = (rows) => {
+  settingsDb.getAll = async () => Object.entries(rows).map(([key, value]) => ({ key, value }))
+  settingsDb.get = async (key) => (key in rows ? rows[key] : null)
+}
+
+test('the public settings payload no longer carries gameAccountSignup', async () => {
+  // Configured as it would be on a live instance that had the feature on. The
+  // row is still there and still readable — it is simply not core's to interpret.
+  withRows({ site_title: 'Test', game_account_signup: 'hybrid' })
+  const out = await settings.getPublic()
+  assert.equal('gameAccountSignup' in out, false)
+})
+
+test('and the raw row is still there for the module to read', async () => {
+  // The load-bearing half. Renaming or dropping the key would silently reset
+  // every configured instance to `disabled`, with players reporting that signup
+  // stopped working as the only clue.
+  withRows({ game_account_signup: 'hybrid' })
+  assert.equal(await settings.get('game_account_signup'), 'hybrid')
+})
+
+test('the rest of the public payload is unchanged', async () => {
+  // The assertion the deletion actually needed: three clients read this object
+  // and none of them are in this repo. Registration flags are the near
+  // neighbour — same shape, same file, same derived-from-a-mode pattern — and
+  // the one most likely to be taken along by an over-eager edit.
+  withRows({
+    site_title: 'Test',
+    player_registration: 'both',
+    game_account_signup: 'hybrid',
+  })
+  const out = await settings.getPublic()
+  assert.deepEqual(out.registration, { password: true, sso: true })
+  assert.equal(out.site_title, 'Test')
+})
+
+test('core no longer exports the game-signup policy', () => {
+  // A leftover export is a leftover consumer waiting to happen, and the module
+  // has its own copy now. `ctx.settings` is three functions and never included
+  // these, so nothing outside core could have been using them.
+  for (const name of ['GAME_SIGNUP_KEY', 'GAME_SIGNUP_MODES', 'getGameSignupMode', 'isGameAccountSignupEnabled']) {
+    assert.equal(name in settings, false, `settings still exports ${name}`)
+  }
+})