feat: steadier live updates and notices for public proposals

- The web pings the live connection, reconnects when it goes quiet and
  reloads what each screen shows after reconnecting.
- Dropping a card on a column it cannot go to puts it back.
- Owners and admins get a notice when a proposal arrives.
- The proposal limit lives in Redis, so it holds across instances.
- REST tells whether I voted; pasted images leave the attachment list.
- Deleting a project removes its Git integration; no lint warnings left.
- Reactions and the blocked badge are components of their own.
- Docs: what is done and what is left (chapter 10), Word and PDF.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libs/api/tracker/infrastructure/src/lib/redis/redis-rate-limit.store.ts

@@ -0,0 +1,19 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { REDIS_CLIENT } from '@task-stream/api/shared/infrastructure';
+import { RateLimitStore } from '@task-stream/api/tracker/application';
+import Redis from 'ioredis';
+
+/** A fixed window per key: the first hit opens it, it expires on its own. */
+@Injectable()
+export class RedisRateLimitStore extends RateLimitStore {
+  constructor(@Inject(REDIS_CLIENT) private readonly redis: Redis) {
+    super();
+  }
+
+  async hit(key: string, windowMs: number): Promise<number> {
+    const name = `task-stream:rate:${key}`;
+    const count = await this.redis.incr(name);
+    if (count === 1) await this.redis.pexpire(name, windowMs);
+    return count;
+  }
+}

libs/api/tracker/infrastructure/src/lib/tracker-infrastructure.module.ts

@@ -32,6 +32,7 @@ import {
   UpsertMaterializedReleaseRepository,
   UpsertMaterializedTimelineRepository,
   UserDirectory,
+  RateLimitStore,
 } from '@task-stream/api/tracker/application';
 import { IdentityUserDirectory } from './identity/identity-user-directory';
 import {
@@ -64,6 +65,7 @@ import {
 import { PostgresReleaseIssuesRepository } from './postgres/release-issues.repository';
 import { PostgresTrackerStreamsRepository } from './postgres/tracker-streams.repository';
 import { RedisChangeFeed } from './realtime/redis-change-feed';
+import { RedisRateLimitStore } from './redis/redis-rate-limit.store';
 import { MongoNotificationsRepository } from './mongo/notifications.repository';
 import { MongoSavedFiltersRepository } from './mongo/saved-filters.repository';
 import { MongoGitIntegrationsRepository } from './mongo/git-integrations.repository';
@@ -144,6 +146,7 @@ const PORTS = [
   { provide: NotificationMailer, useClass: SmtpNotificationMailer },
   // Realtime → Redis pub/sub
   { provide: ChangeFeed, useClass: RedisChangeFeed },
+  { provide: RateLimitStore, useClass: RedisRateLimitStore },
   // Identity context (anti-corruption layer)
   { provide: UserDirectory, useClass: IdentityUserDirectory },
 ];