feat(admin): display running version in footer and /health

Inline package.json version at bundle time via src/config/version.ts
(resolveJsonModule), surface it in the shared admin/status footer and
add it to the /health JSON so self-hosters can tell which build runs.

Co-Authored-By: Claude Opus 4.7 <[email protected]>

src/config/version.ts

@@ -0,0 +1,8 @@
+import pkg from "../../package.json";
+
+/**
+ * The running app version, inlined from package.json at bundle time (the Worker
+ * has no filesystem at runtime). Surfaced in the admin/status footer and the
+ * /health JSON so a self-hoster can tell which build is deployed.
+ */
+export const APP_VERSION: string = pkg.version;