Auto-wake agents on btmsg and fix unwanted auto-scroll

- Add btmsg inbox polling (10s) to AgentSession so agents wake when
  they receive messages from other agents (not just admin DMs)
- Remove automatic setActiveProject on agent activation to prevent
  focus stealing from the user
- Use untrack() in ProjectGrid scroll effect so agent re-renders
  don't trigger unwanted scrollIntoView

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

v2/src/lib/components/Workspace/AgentSession.svelte

@@ -27,6 +27,7 @@
   import { getProvider, getDefaultProviderId } from '../../providers/registry.svelte';
   import { loadAnchorsForProject } from '../../stores/anchors.svelte';
   import { getSecret } from '../../adapters/secrets-bridge';
+  import { getUnreadCount } from '../../adapters/btmsg-bridge';
   import { getWakeEvent, consumeWakeEvent, updateManagerSession } from '../../stores/wake-scheduler.svelte';
   import { SessionId, ProjectId } from '../../types/ids';
   import AgentPane from '../Agent/AgentPane.svelte';
@@ -136,11 +137,43 @@
     stopAgent(sessionId).catch(() => {});
   });
 
+  // btmsg inbox polling — auto-wake agent when it receives messages from other agents
+  let msgPollTimer: ReturnType<typeof setInterval> | null = null;
+  let lastKnownUnread = 0;
+
+  function startMsgPoll() {
+    if (msgPollTimer) clearInterval(msgPollTimer);
+    msgPollTimer = setInterval(async () => {
+      if (contextRefreshPrompt) return; // Don't queue if already has a pending prompt
+      try {
+        const count = await getUnreadCount(project.id as unknown as AgentId);
+        if (count > 0 && count > lastKnownUnread) {
+          lastKnownUnread = count;
+          const wakeMsg = project.isAgent
+            ? `[New Message] You have ${count} unread message(s). Check your inbox with \`btmsg inbox\` and respond appropriately.`
+            : `[New Message] You have ${count} unread message(s). Check your inbox and respond.`;
+          contextRefreshPrompt = wakeMsg;
+          logAuditEvent(
+            project.id as unknown as AgentId,
+            'wake_event',
+            `Agent woken by ${count} unread btmsg message(s)`,
+          ).catch(() => {});
+        } else if (count === 0) {
+          lastKnownUnread = 0;
+        }
+      } catch {
+        // btmsg not available, ignore
+      }
+    }, 10_000); // Check every 10s
+  }
+
   // Start timer and clean up
   startReinjectionTimer();
+  startMsgPoll();
   onDestroy(() => {
     if (reinjectionTimer) clearInterval(reinjectionTimer);
     if (wakeCheckTimer) clearInterval(wakeCheckTimer);
+    if (msgPollTimer) clearInterval(msgPollTimer);
     unsubAgentStart();
     unsubAgentStop();
   });

v2/src/lib/components/Workspace/GroupAgentsPanel.svelte

@@ -64,7 +64,6 @@
       await setAgentStatus(agent.id, newStatus);
       await pollBtmsg(); // Refresh immediately
       if (newStatus === 'active') {
-        setActiveProject(agent.id);
         emitAgentStart(agent.id);
       } else {
         emitAgentStop(agent.id);

v2/src/lib/components/Workspace/ProjectGrid.svelte

@@ -1,5 +1,5 @@
 <script lang="ts">
-  import { onMount, onDestroy } from 'svelte';
+  import { onMount, onDestroy, untrack } from 'svelte';
   import { getAllWorkItems, getActiveProjectId, setActiveProject } from '../../stores/workspace.svelte';
   import ProjectBox from './ProjectBox.svelte';
 
@@ -15,15 +15,17 @@
   // Track slot elements for auto-scroll
   let slotEls = $state<Record<string, HTMLElement>>({});
 
-  // Auto-scroll to active project when it changes
+  // Auto-scroll to active project only when activeProjectId changes
+  // (untrack slotEls so agent re-renders don't trigger unwanted scrolls)
   $effect(() => {
     const id = activeProjectId;
     if (!id) return;
+    untrack(() => {
       const el = slotEls[id];
       if (!el) return;
-    // Use smooth scroll; block: nearest avoids jumping if already visible
       el.scrollIntoView({ behavior: 'smooth', block: 'nearest', inline: 'nearest' });
     });
+  });
 
   let observer: ResizeObserver | undefined;