feat: sign posted comments with a random team member

Replaces the placeholder you author with a random pick from the project roster so the demo feed shows Roberto Mirae Jonathan and Andrés instead of a generic stand-in. The pick happens per post and is reused for the Hub entry so the two views stay consistent.

frontend/src/pages/WatchPage.tsx

@@ -18,6 +18,7 @@ import type {
 import {
   formatPct,
   newId,
+  randomTeamMember,
   randomUsername,
   relativeTime,
   toxicityColor,
@@ -86,9 +87,10 @@ export function WatchPage() {
     setPosting(true);
     try {
       const analysis = result ?? (await predict(text, threshold));
+      const author = randomTeamMember();
       const item: CommentItem = {
         id: newId(),
-        user: t.watch.you,
+        user: author,
         text,
         time: t.watch.justNow,
         is_toxic: analysis.is_toxic,
@@ -98,7 +100,7 @@ export function WatchPage() {
       };
       setSessionComments((prev) => [...prev, item]);
       addHubEntry({
-        user: `@${t.watch.you}`,
+        user: `@${author}`,
         snippet: text.slice(0, 45),
         score: analysis.probability,
         action: analysis.is_toxic

frontend/src/utils/toxicity.ts

@@ -13,6 +13,17 @@ export function newId(): string {
   return `${Date.now()}-${Math.random().toString(36).slice(2, 9)}`;
 }
 
+export const TEAM_MEMBERS = [
+  "Roberto Molero",
+  "Mirae Kang",
+  "Jonathan Brasales",
+  "Andrés Torrez",
+] as const;
+
+export function randomTeamMember(): string {
+  return TEAM_MEMBERS[Math.floor(Math.random() * TEAM_MEMBERS.length)];
+}
+
 const RTF = new Intl.RelativeTimeFormat("es", { numeric: "auto" });
 
 const TIME_UNITS: Array<[Intl.RelativeTimeFormatUnit, number]> = [