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/web/routes/conversations.ts

@@ -32,13 +32,20 @@ export function createConversationsRouter(ctx: WebContext): Router {
       return;
     }
     try {
-      // Pull in any new activity from the homeserver before we read the cache,
-      // so a stale "waiting for them to reply" view picks up the reply they
-      // already sent. Cheap (~one /sync call) and queued behind any in-flight sync.
-      try {
-        await ctx.services.chat.refreshTopChats();
-      } catch (err) {
-        ctx.logger.warn('Pre-open delta sync failed:', err);
+      // If a sync is already in flight (e.g. a Full sync the user kicked off
+      // from the dashboard), don't queue *another* delta + lazy-load behind it
+      // — that's what makes the modal sit on "Loading…" for minutes. Render
+      // from cache and let the frontend show a "sync in progress" banner; the
+      // user can reopen once it's done.
+      const syncStatus = ctx.services.chat.getSyncStatus();
+      const syncInFlight = syncStatus.syncing;
+
+      if (!syncInFlight) {
+        try {
+          await ctx.services.chat.refreshTopChats();
+        } catch (err) {
+          ctx.logger.warn('Pre-open delta sync failed:', err);
+        }
       }
       const conversation = await findConversation(decodeURIComponent(req.params.id));
       if (!conversation) {
@@ -53,7 +60,9 @@ export function createConversationsRouter(ctx: WebContext): Router {
         ? conversation.messages[conversation.messages.length - 1].timestamp
         : 0;
       const hasNewerActivity = (conversation.lastMessageTime ?? 0) > cachedLastTs;
-      if (!conversation.messages || conversation.messages.length === 0 || hasNewerActivity) {
+      const needsLazyLoad =
+        !conversation.messages || conversation.messages.length === 0 || hasNewerActivity;
+      if (needsLazyLoad && !syncInFlight) {
         try {
           await ctx.services.chat.loadConversationDetails(conversation);
           await ctx.services.chat.saveCacheExternal();
@@ -88,7 +97,17 @@ export function createConversationsRouter(ctx: WebContext): Router {
         ctx.logger.warn(`Failed to look up triggering post for ${conversation.username}:`, err);
       }
 
-      res.json({ ...conversation, triggeringPost });
+      res.json({
+        ...conversation,
+        triggeringPost,
+        syncInProgress: syncInFlight
+          ? {
+              kind: syncStatus.syncingKind,
+              progress: syncStatus.progress,
+              staleMessages: needsLazyLoad,
+            }
+          : null,
+      });
     } catch (error) {
       ctx.logger.error('Failed to fetch conversation:', error);
       res.status(500).json({ error: String(error) });