Oh man that's a lot of changes.

client/public/data.js

@@ -1,7 +1,7 @@
 // coms/client/public/data.js
 // Data module: holds the in‐memory threads, notices and reply state
 
-// Map of all messages and notices by ID
+// Map of all messages and notices by ID (string IDs)
 // Client’s own session ID
 let myId = null;
 const threads = new Map();
@@ -9,28 +9,28 @@ const threads = new Map();
 // Map of connected users by unique ID
 const users = new Map();
 
-// Ordered list of root‐level IDs (messages and notices)
+// Ordered list of root‐level IDs (messages and notices, stored as strings)
 const rootIds = [];
 
 // Negative counter to generate unique IDs for notices
 let noticeCounter = -1;
 
-// ID of the message we’re currently replying to (or null)
+// ID of the message we’re currently replying to (string or null)
 let replyTo = null;
 
-// ID of the message currently focused for navigation (or null)
+// ID of the message currently focused for navigation (string or null)
 let focusedId = null;
 
 /**
  * Set the focused message ID (or null to clear).
- * @param {number|null} id
+ * @param {string|null} id
  */
 function setFocused(id) {
   focusedId = id;
 }
 /**
  * Get the currently focused message ID.
- * @returns {number|null}
+ * @returns {string|null}
  */
 function getFocused() {
   return focusedId;
@@ -46,7 +46,7 @@ function clearFocused() {
 
 /**
  * Register a user with their unique ID.
- * @param {number} id
+ * @param {string} id
  * @param {string} name
  */
 function addUser(id, name) {
@@ -55,7 +55,7 @@ function addUser(id, name) {
 
 /**
  * Remove a user by their ID.
- * @param {number} id
+ * @param {string} id
  */
 function removeUser(id) {
   users.delete(id);
@@ -63,7 +63,7 @@ function removeUser(id) {
 
 /**
  * Update a user’s name.
- * @param {number} id
+ * @param {string} id
  * @param {string} name
  */
 function updateUser(id, name) {
@@ -72,7 +72,7 @@ function updateUser(id, name) {
 
 /**
  * Get a list of {id, name} objects for all users.
- * @returns {{id:number, name:string}[]}
+ * @returns {{id:string, name:string}[]}
  */
 function getUsers() {
   return Array.from(users.entries()).map(([id, name]) => ({ id, name }));
@@ -95,14 +95,31 @@ function getGroupedUsers() {
 
 /**
  * Add a new chat message to the thread structure.
- * @param {{id: number, username: string, content: string, ts: number, parent?: number}} msg
+ * @param {{id: string|number, username: string, content: string, ts: number, parent?: string|number|null, authorId?: string|number|null}} msg
  */
-function addMessage({ id, username, content, ts, parent = null }) {
-  threads.set(id, { id, username, content, ts, parent, children: [] });
-  if (parent !== null && threads.has(parent)) {
-    threads.get(parent).children.push(id);
+function addMessage({
+  id,
+  username,
+  content,
+  ts,
+  parent = null,
+  authorId = null,
+}) {
+  const sid = String(id);
+  const sparent = parent === null ? null : String(parent);
+  threads.set(sid, {
+    id: sid,
+    username,
+    authorId: authorId === null ? null : String(authorId),
+    content,
+    ts,
+    parent: sparent,
+    children: [],
+  });
+  if (sparent !== null && threads.has(sparent)) {
+    threads.get(sparent).children.push(sid);
   } else {
-    rootIds.push(id);
+    rootIds.push(sid);
   }
 }
 
@@ -112,7 +129,7 @@ function addMessage({ id, username, content, ts, parent = null }) {
  */
 function addNotice(content) {
   const ts = Math.floor(Date.now() / 1000);
-  const id = noticeCounter--;
+  const id = String(noticeCounter--);
   threads.set(id, {
     id,
     username: "",
@@ -132,40 +149,41 @@ function clearData() {
   rootIds.length = 0;
   noticeCounter = -1;
   replyTo = null;
+  users.clear();
 }
 
-/** @returns {Map<number,object>} The threads map. */
+/** @returns {Map<string,object>} The threads map. */
 function getThreads() {
   return threads;
 }
 
-/** @returns {number[]} The ordered list of root‐level IDs. */
+/** @returns {string[]} The ordered list of root‐level IDs. */
 function getRootIds() {
   return rootIds;
 }
 
 /**
  * Set this client’s own session ID.
- * @param {number} id
+ * @param {string|number} id
  */
 function setMyId(id) {
-  myId = id;
+  myId = String(id);
 }
 
 /**
  * Get this client’s own session ID.
- * @returns {number|null}
+ * @returns {string|null}
  */
 function getMyId() {
   return myId;
 }
 
-/** @returns {number|null} The current reply‐to ID. */
+/** @returns {string|null} The current reply‐to ID. */
 function getReplyTo() {
   return replyTo;
 }
 
-/** @param {number|null} id — Set the current reply‐to ID. */
+/** @param {string|null} id — Set the current reply‐to ID. */
 function setReplyTo(id) {
   replyTo = id;
 }