v3: various improvements and fixes to real-time updates

api/model/interfaces.ts

@@ -658,6 +658,11 @@ export interface NotificationCreatedMessage {
 export interface ErrorMessage {
   type: "error";
   message?: string;
+  // Context for optimistic-action failures so the client can revert the exact
+  // pending vote/like immediately instead of waiting for its ACK timeout.
+  dumpId?: string;
+  commentId?: string;
+  action?: "cast" | "remove";
 }
 
 export interface ForceLogoutMessage {

api/routes/avatars.ts

@@ -1,7 +1,10 @@
 import { Router } from "@oak/oak";
 import { authMiddleware } from "../middleware/auth.ts";
 import { getUserById, updateUserAvatar } from "../services/user-service.ts";
-import { updateClientAvatar } from "../services/ws-service.ts";
+import {
+  broadcastUserUpdated,
+  updateClientAvatar,
+} from "../services/ws-service.ts";
 import { APIErrorCode, APIException } from "../model/interfaces.ts";
 import {
   AVATARS_DIR,
@@ -45,6 +48,11 @@ router.post("/api/avatars/me", authMiddleware, async (ctx) => {
   updateClientAvatar(authPayload.userId, mime);
 
   const { passwordHash: _, ...publicUser } = getUserById(authPayload.userId);
+  // Let every client refresh this user's avatar wherever it's shown (feeds,
+  // comments, OP, profiles) — not just the presence row. updated_at, bumped on
+  // the avatar write, doubles as the cache-busting version.
+  const { email: _email, ...broadcastUser } = publicUser;
+  broadcastUserUpdated(broadcastUser);
   ctx.response.status = 200;
   ctx.response.body = { success: true, data: publicUser };
 });

api/routes/ws.ts

@@ -153,7 +153,7 @@ function handleVote(
     broadcastVoteUpdate(dumpId, newCount, client.userId, action);
   } catch (err) {
     const message = err instanceof APIException ? err.message : "Vote failed";
-    socket.send(JSON.stringify({ type: "error", message }));
+    socket.send(JSON.stringify({ type: "error", message, dumpId, action }));
   }
 }
 
@@ -186,7 +186,7 @@ function handleCommentLike(
     broadcastCommentLikeUpdate(commentId, newCount, client.userId, action);
   } catch (err) {
     const message = err instanceof APIException ? err.message : "Like failed";
-    socket.send(JSON.stringify({ type: "error", message }));
+    socket.send(JSON.stringify({ type: "error", message, commentId, action }));
   }
 }
 

api/services/notification-service.ts

@@ -169,13 +169,18 @@ export function notifyUserFollowersNewDump(
   const createdAt = new Date().toISOString();
   const sourceKey = `dump:${dumpId}`;
 
-  // Batch INSERT all follower notifications in a single statement
-  const params: (string | number | null)[] = [];
-  const placeholders: string[] = [];
+  // Insert per follower so we can broadcast only the rows that were actually
+  // created (INSERT OR IGNORE skips followers who already have this dump's
+  // notification) and reuse each persisted id in the live event — otherwise a
+  // later refetch would dedupe against a mismatched id and show a duplicate.
+  const insert = db.prepare(
+    `INSERT OR IGNORE INTO notifications (id, user_id, type, data, read, created_at, source_key)
+     VALUES (?, ?, ?, ?, 0, ?, ?);`,
+  );
+
   for (const row of followerRows) {
     const id = crypto.randomUUID();
-    placeholders.push("(?, ?, ?, ?, 0, ?, ?)");
-    params.push(
+    const result = insert.run(
       id,
       row.follower_id,
       "user_dump_posted",
@@ -183,19 +188,11 @@ export function notifyUserFollowersNewDump(
       createdAt,
       sourceKey,
     );
-  }
-
-  const result = db.prepare(
-    `INSERT OR IGNORE INTO notifications (id, user_id, type, data, read, created_at, source_key)
-     VALUES ${placeholders.join(", ")};`,
-  ).run(...params);
-
-  if ((result.changes as number) > 0) {
-    for (const row of followerRows) {
+    if ((result.changes as number) > 0) {
       sendToUser(row.follower_id, {
         type: "notification_created",
         notification: {
-          id: crypto.randomUUID(),
+          id,
           userId: row.follower_id,
           type: "user_dump_posted",
           data,