feat(pet): cleared alerts stay cleared, contextual bubbles, i18n, moments, chat window

- Fix: an errored session alerted on every update, and Clear alerts only
  dropped it in memory, so its next update (or a reload) brought the alert
  straight back. An error now alerts on the transition into error only;
  cleared sessions are remembered (agenthub.pet.dismissedErrors) and stay
  quiet until they recover and fail anew.
- Quips, greetings, notifications and Ask answers move to i18n (EN/VI);
  Ask understands Vietnamese keywords and names the sessions it counts.
- The pet goes by the worn pet's name; click it in the panel to rename
  (agenthub.pet.names, synced to the account).
- Bubbles name the session they are about, with an Open button (never a
  resume); a burst of the same event coalesces into one count.
- Moments: a new session waves, a finish hops, a subagent peeks, a wait taps,
  an error flinches — on Sagi, Codex sprites and still images. Idle fidgets,
  a once-per-session greeting, a "Needs you" list, an amber waiting dot.
- Pat (heart button, Ask, or stroking the pet) reacts on the pet itself, so
  it shows while the panel or chat is open.
- Panel drops Run Claude / Activity / Sessions / Errored.
- Ask hands off to a chat window (PetChat) on the default AI tool
  (Claude/Codex): transcript as bubbles, follow-ups and CLI menus through an
  off-screen attached terminal; no new server route.

Verified on HEAD + this diff in a clean worktree: tsc -b, the full client
suite (1334/1335; the one failure, ConversationView.follow, is flaky under
load and passes 3/3 alone) and server me-prefs.test.js.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

client/src/components/Sagi/PetSprite.tsx

@@ -8,7 +8,9 @@
  * timings; a moment (waving, jumping, failed, review) plays three times and
  * settles into idle, a condition loops. An `action` (dragged left/right,
  * hovered) plays the run-left/run-right or waving row over the mood's, like
- * Codex's own pet, and a v2 pet at idle holds the gaze pose `gaze` names. An
+ * Codex's own pet; a `moment` (a new session waves, a finish jumps, an error
+ * fails, a wait waits, a new subagent reviews — `useSagiBrain`) plays its row
+ * over the mood's, under the action; a v2 pet at idle holds the gaze pose `gaze` names. An
  * uploaded image is shown still and bobs with the same `data-mood` CSS as
  * Sagi. Reduced motion holds the row's first frame. A sprite that fails to
  * load (deleted from another browser) calls `onBroken`, so the mascot falls
@@ -18,7 +20,7 @@
 
 import { useEffect, useState } from "react";
 import { api } from "../../lib/api";
-import type { Mood } from "./brain";
+import type { Mood, PetMoment } from "./brain";
 
 const CELL = { w: 192, h: 208 };
 const COLS = 8;
@@ -58,12 +60,16 @@ const ROW: Record<Mood, number> = {
 /** What the user is doing to the pet, which outranks its mood. */
 export type PetAction = "run-left" | "run-right" | "wave";
 const ACTION_ROW: Record<PetAction, number> = { "run-right": 1, "run-left": 2, wave: 3 };
+/** A moment's row: wave, jump, failed, waiting, review. It outranks the mood,
+ *  and the user's own action outranks it. */
+const MOMENT_ROW: Record<PetMoment, number> = { wave: 3, jump: 4, fail: 5, wait: 6, review: 8 };
 
 export function PetSprite({
   id,
   kind,
   mood,
   action,
+  moment,
   gaze,
   size,
   reducedMotion,
@@ -73,6 +79,7 @@ export function PetSprite({
   kind: "codex" | "image";
   mood: Mood;
   action?: PetAction | null;
+  moment?: PetMoment | null;
   /** Gaze pose 0–15 (0 = up, clockwise), or none. Only a v2 sheet has them. */
   gaze?: number | null;
   size: number;
@@ -80,8 +87,8 @@ export function PetSprite({
   onBroken: () => void;
 }) {
   const url = api.pets.spriteUrl(id);
-  const row = action ? ACTION_ROW[action] : (ROW[mood] ?? 0);
-  const sleeping = !action && mood === "sleeping";
+  const row = action ? ACTION_ROW[action] : moment ? MOMENT_ROW[moment] : (ROW[mood] ?? 0);
+  const sleeping = !action && !moment && mood === "sleeping";
   // The cell on show, tagged with the row it was played for: a cell left over
   // from the previous row (say column 7 of a run) is never drawn on the next.
   const [cell, setCell] = useState({ of: row, row, col: 0 });
@@ -132,6 +139,7 @@ export function PetSprite({
         src={url}
         alt=""
         data-mood={mood}
+        data-moment={moment ?? undefined}
         className="sagi-pet-image"
         width={size}
         height={size}
@@ -141,7 +149,8 @@ export function PetSprite({
       />
     );
   }
-  const pose = gaze != null && rows > GAZE_ROW && !action && mood === "idle" ? gaze : null;
+  const pose =
+    gaze != null && rows > GAZE_ROW && !action && !moment && mood === "idle" ? gaze : null;
   const shown =
     pose != null
       ? { row: GAZE_ROW + Math.floor(pose / COLS), col: pose % COLS }