feat: the module skeleton and every bundle seam

module-rust, id 'rust', built from the Integration Kit's template. Phase 1's job
is the kit's own argument: get every seam working at once with almost nothing in
them, so that afterwards you break exactly one at a time.

What is here:

* /rust on all three tiers, because the loader holds module.json's mounts against
  what is registered in BOTH directions -- so the declaration and the
  registration land together or not at all. The player tier is honestly thin: it
  answers the server list on the authenticated tier, delegating to the same model
  the public tier uses so the two cannot drift while they are meant to be the
  same. It is the address the app will call, registered now rather than moved
  later.
* Two tables. rust_servers is configuration an operator writes; rust_server_state
  is what a sidecar reported. Separate tables because they have different
  writers, lifetimes and audiences -- and because purging observed state while
  keeping the configuration is a thing an operator will want.
* Per-server sidecar tokens through ctx.secretBox, write-only in the API. The
  admin list reports hasToken and never the credential, and an empty token on a
  save leaves the stored one alone -- a form that posts its own blank field would
  otherwise erase a credential every time somebody renamed a server.
* A real sidecar client. It never throws: every call answers {ok, status, data},
  and the status is what tells a wrong URL from a wrong token from a mismatched
  protocol -- all three present as 'the site says my server is offline' and each
  has a different fix.
* The five guards, green: check:imports, check:swagger, check:externals, and both
  suites.

What is deliberately NOT registered: the Team provider, triggers, audiences,
engagement seeds, notification streams, the four event catalogues, and the two
extension slots. Each arrives with the phase that has something real to put in
it, and a test asserts their absence so that removing it is deliberate. A
declared trigger nothing emits and a declared slot nothing fills are both
surfaces an operator can configure and then wait on, which is worse than an
absent one because the absence is visible.

Two corrections to the kit's template, both feedback for a later phase:

* registration.test.js read one page BY NAME to check declared slots are
  rendered, so a module declaring none dies on ENOENT before reaching the loop
  that would have been empty. It now scans every file under src/routes.
* test/_fakes.js supplied validator: {}. An admin router that builds validation
  chains at file scope cannot be required with that, so the fake holds the real
  express-validator -- for the same reason it holds a real express Router.

The kit was right about noGameConnection.test.js: its header predicts that a
module adding a sidecar client will see the check go red, names sidecarClient.js
as the file to allow, and says narrow it rather than delete it. That is exactly
what happened on the first run, and the fix was the one line the header names.

Installed into a real core and verified: the module reaches 'started', publishes
its capability, serves its chunk, and renders a server whose server.hello
originated in a live Rust server.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016wDDVXWMDz82WqE1i969r4

client/src/entry.jsx

@@ -0,0 +1,78 @@
+// ── The client entry point ────────────────────────────────────────────────
+//
+// Core serves `dist/entry.js` from this module's directory and injects it into
+// its own HTML as a same-origin `<script type="module" src>` before `</body>`.
+// This file registers what the module has; core renders it. Normative:
+// MODULE_API.md §3.3.
+//
+// **Registration is synchronous and happens at evaluation time.** Module scripts
+// are deferred, so this runs after core's bundle — which is where `window.__rg`
+// is published — and before core's first render. There is no subscription and no
+// late registration: a module that registered asynchronously would register after
+// the route table had been read, and the symptom is a page that redirects home
+// with nothing logged anywhere.
+//
+// So everything below is a plain top-level call and every page is a STATIC
+// import. Lazy-loading the routes is the natural instinct for a chunk that grows,
+// and it is the one thing this seam cannot have.
+
+import { registry, coreApiVersion } from './core.js'
+
+import Servers from './routes/public/Servers.jsx'
+
+// The module id, exactly as `module.json` spells it. Core keys the registry by it
+// and prefixes every route path with it.
+const ID = 'rust'
+
+// ── Routes ────────────────────────────────────────────────────────────────
+//
+// Paths are relative to the module's namespace and core prefixes them. Whatever
+// is written here, a public route lands at `/<id>/<path>`, an admin route at
+// `/admin/<id>/<path>` and a player route at `/player/<id>/<path>`. A module
+// cannot write the segment its routes hang under, which is the point: two modules
+// installed side by side cannot collide, and an operator can see from a URL which
+// module served it.
+//
+// So this page is at `/rust/servers`.
+//
+// **Note what is NOT here: an auth wrapper.** `gate: { roles: [...] }` is
+// available and core applies it as its own `RoleGate`; supplying your own is not
+// possible, because the sidebar and the route table have to agree about who may
+// see what, and they only do if one thing decides.
+//
+// R8's landing page is the server list, and `/rust/servers/:id` hangs beneath it.
+// The detail route is a later phase's, and it is deliberately not stubbed here: a
+// registered route that renders nothing is a 200 with a blank page, which is
+// worse than the 404 an unregistered one gives.
+registry.registerRoutes(ID, {
+  public: [{ path: 'servers', element: <Servers /> }],
+})
+
+// ── Nav ───────────────────────────────────────────────────────────────────
+//
+// A registered row is an ORDINARY row from here on. It interleaves into core's
+// own navigation, and an operator can reorder it, relabel it or hide it from the
+// admin nav editor exactly as they can core's — because the interleave happens
+// before the override merge, and the override layer is keyed by `to`.
+//
+// Three fields worth knowing before you need them:
+//
+//   • `order` places the row among core's, which are keyed by their index. A row
+//     with NO order appends after them, rather than defaulting to 0 — otherwise
+//     "I didn't ask for a position" would mean "put me first".
+//   • `group` (admin sidebar) names an existing core group; an unknown name
+//     appends a new group at the end rather than dropping the row.
+//   • `icon` is a component, and core supplies no fallback. Public header rows
+//     carry no icons, so there is none here — but an admin or player row without
+//     one is the only row in its sidebar with no glyph, which reads as breakage.
+registry.registerNav(ID, {
+  area: 'public',
+  items: [{ label: 'Servers', to: '/rust/servers' }],
+})
+
+// `module.json`'s `coreApi` range was checked by the loader before this file was
+// ever served, so there is nothing to re-check here. Log it anyway: a mismatch
+// between the core that validated the manifest and the core that published this
+// global is otherwise invisible from the browser, which is where the client half
+// actually fails.
+console.info(`[${ID}] registered against core API ${coreApiVersion}`)