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/presenters/src/lib/http/proposal-limiter.ts

@@ -1,33 +1,24 @@
 import { HttpException, HttpStatus, Injectable } from '@nestjs/common';
+import { RateLimitStore } from '@task-stream/api/tracker/application';
 
 /** Proposals from one address within the window. */
 const LIMIT = 5;
 const WINDOW_MS = 15 * 60_000;
 
 /**
- * Keeps one address from flooding a project with proposals. In memory:
- * enough for one instance, and an approximation with several (each counts
- * its own), which is fine for what it guards against.
+ * Keeps one address from flooding a project with proposals. Counted in
+ * Redis, so the limit holds across every instance of the API.
  */
 @Injectable()
 export class ProposalLimiter {
-  private readonly sent = new Map<string, number[]>();
+  constructor(private readonly store: RateLimitStore) {}
 
-  take(address: string): void {
-    const now = Date.now();
-    const recent = (this.sent.get(address) ?? []).filter(
-      (at) => now - at < WINDOW_MS,
-    );
-    if (recent.length >= LIMIT)
+  async take(address: string): Promise<void> {
+    const count = await this.store.hit(`proposals:${address}`, WINDOW_MS);
+    if (count > LIMIT)
       throw new HttpException(
         'Too many proposals from here; try again in a few minutes',
         HttpStatus.TOO_MANY_REQUESTS,
       );
-    recent.push(now);
-    this.sent.set(address, recent);
-    // Forget quiet addresses now and then, so the map does not grow forever.
-    if (this.sent.size > 10_000)
-      for (const [key, times] of this.sent)
-        if (times.every((at) => now - at >= WINDOW_MS)) this.sent.delete(key);
   }
 }