feat(v1.1.6): realtime channels + v1.1.5 follow-ups + version bumps

Server-side realtime SSE on per-app pub/sub topics, plus the three
v1.1.5 follow-ups and the version bumps.

Realtime:
- topics registry (0021) + admin endpoints + Capability::AppTopicManage
  (-> app:admin; no new scope).
- GET /realtime/topics/{topic} SSE endpoint (orchestrator-core data
  plane): Host -> app, RealtimeAuthority gate (404 missing/internal,
  401 bad/absent token), broadcast::Receiver stream + heartbeat.
- RealtimeBroadcaster / RealtimeEvent / RealtimeAuthority traits
  (picloud-shared); InProcessBroadcaster + GC (orchestrator-core);
  DB-backed RealtimeAuthorityImpl (manager-core). Publish path fans out
  to in-process subscribers after the durable outbox commit (best-effort,
  panic-isolated).
- HMAC subscriber tokens (subscriber_token.rs) + app_secrets table (0022)
  + pubsub::subscriber_token SDK (schema 1.6 -> 1.7). TTL clamp + env
  overrides.
- Dashboard Topics tab (register/list/edit/delete, prominent external
  badge, flip confirmation).

v1.1.5 follow-ups:
- Empty blobs accepted (NewFile/FileUpdate::validate) + round-trip test.
- Orphan *.tmp.* sweeper (spawn_files_orphan_sweep).
- Dispatcher e2e tests, one per trigger kind (DATABASE_URL-gated).

Versions: workspace 1.1.6, SDK 1.7, dashboard 0.12.0. Schema-snapshot
golden re-blessed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/shared/src/version.rs

@@ -49,7 +49,16 @@ pub const PRODUCT_VERSION: &str = env!("CARGO_PKG_VERSION");
 /// publish-time fan-out and `ctx.event.pubsub` for pubsub-trigger
 /// handlers. The `Services` bundle gains `files: Arc<dyn FilesService>`
 /// and `pubsub: Arc<dyn PubsubService>`.
-pub const SDK_VERSION: &str = "1.6";
+///
+/// 1.7 additions (v1.1.6): `pubsub::subscriber_token(topics, ttl)` —
+/// mints an HMAC-signed realtime subscriber token for externally-
+/// subscribable topics (requires an authenticated principal). This is
+/// the only new script-visible surface; the rest of the release is
+/// server-side (the SSE `/realtime/topics/{topic}` endpoint; the
+/// `RealtimeBroadcaster` / `RealtimeEvent` / `RealtimeAuthority` traits;
+/// the `topics` registry + admin endpoints; the `@picloud/client`
+/// TypeScript package).
+pub const SDK_VERSION: &str = "1.7";
 
 /// HTTP API major version. Appears in URL paths as `/api/v{N}/...`.
 /// Bump (new integer + new URL prefix) when the request/response