Blur gallery images by default, sync progress UI, and add chat/monitor tests

- Blur NSFW media gallery images until hover/reveal
- Surface chat sync progress in the dashboard header
- Extend chat service, cache, and monitor with delta-media handling
- Add tests for chat cooldown, delta media, and monitor flows

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/services/chat/cache.ts

@@ -1,7 +1,7 @@
 import fs from 'fs/promises';
 import path from 'path';
 import type { Logger } from '../../utils/logger.js';
-import type { ActiveChat, ChatCacheFile } from './types.js';
+import type { ActiveChat, ChatCacheFile, InvitationCooldown } from './types.js';
 
 export interface SyncMarkers {
   nextBatch: string | null;
@@ -22,6 +22,7 @@ export class ChatCache {
   private nextBatch: string | null = null;
   private lastFullSyncAt: number | null = null;
   private lastDeltaSyncAt: number | null = null;
+  private cooldown: InvitationCooldown | null = null;
 
   constructor(private logger: Logger, filePath?: string) {
     this.filePath = filePath ?? path.join(process.cwd(), 'data', 'chat-cache.json');
@@ -61,6 +62,14 @@ export class ChatCache {
     this.lastDeltaSyncAt = at;
   }
 
+  getCooldown(): InvitationCooldown | null {
+    return this.cooldown;
+  }
+
+  setCooldown(cooldown: InvitationCooldown | null): void {
+    this.cooldown = cooldown;
+  }
+
   async load(): Promise<void> {
     try {
       const raw = await fs.readFile(this.filePath, 'utf-8');
@@ -74,6 +83,7 @@ export class ChatCache {
       this.nextBatch = parsed.nextBatch ?? null;
       this.lastFullSyncAt = parsed.lastFullSyncAt ?? null;
       this.lastDeltaSyncAt = parsed.lastDeltaSyncAt ?? null;
+      this.cooldown = parsed.cooldown ?? null;
       this.logger.info(
         `Loaded ${parsed.chats.length} chats from cache` +
           (this.lastFullSyncAt
@@ -89,6 +99,41 @@ export class ChatCache {
     }
   }
 
+  /**
+   * Persist only the cooldown field, preserving whatever chats / sync markers
+   * are already on disk. Used when a rate-limit fires before the in-memory
+   * cache has been populated — a plain `save()` would clobber a prior full
+   * sync with `chats: []` and null markers.
+   */
+  async persistCooldown(): Promise<void> {
+    let existing: ChatCacheFile | null = null;
+    try {
+      const raw = await fs.readFile(this.filePath, 'utf-8');
+      existing = JSON.parse(raw) as ChatCacheFile;
+    } catch (error) {
+      if ((error as NodeJS.ErrnoException).code !== 'ENOENT') {
+        this.logger.warn('Failed to read chat cache for cooldown update:', error);
+      }
+    }
+    const payload: ChatCacheFile = existing
+      ? { ...existing, cooldown: this.cooldown, savedAt: Date.now() }
+      : {
+          version: 1,
+          savedAt: Date.now(),
+          chats: [],
+          nextBatch: null,
+          lastFullSyncAt: null,
+          lastDeltaSyncAt: null,
+          cooldown: this.cooldown,
+        };
+    try {
+      await fs.mkdir(path.dirname(this.filePath), { recursive: true });
+      await fs.writeFile(this.filePath, JSON.stringify(payload, null, 2), 'utf-8');
+    } catch (error) {
+      this.logger.warn('Failed to save chat cache cooldown:', error);
+    }
+  }
+
   async save(chats: ActiveChat[] = this.chats): Promise<void> {
     const payload: ChatCacheFile = {
       version: 1,
@@ -97,6 +142,7 @@ export class ChatCache {
       nextBatch: this.nextBatch,
       lastFullSyncAt: this.lastFullSyncAt,
       lastDeltaSyncAt: this.lastDeltaSyncAt,
+      cooldown: this.cooldown,
     };
     try {
       await fs.mkdir(path.dirname(this.filePath), { recursive: true });