Reduce daemon churn from terminals and archived agents

Decouple terminal list snapshots from workspace status invalidation, and filter archived stored agents before projection so seeded homes do less work.

docs/terminal-activity.md

@@ -17,12 +17,15 @@ TerminalSession
   │     └── onChange(snapshot, previous)    fires only on resolved-state transitions
   │
   └── onActivityChange({ activity, previous })   subscribed in TerminalManager
-        ├── emits terminalsChanged          workspace bucket + tab indicators
+        ├── emits terminalsChanged          terminal list/tab indicators only
         └── subscribeTerminalActivity       per-transition stream for notification policy
+        └── subscribeTerminalWorkspaceContributionChanged  workspace status rollup only
 ```
 
 `TerminalActivityTracker` is the single stateful object per session. It holds `{ state, changedAt }`, starts at unknown (`null`), and fires `onChange` only when the state actually changes.
 
+Terminal directory snapshots (`terminalsChanged`) and workspace contribution changes are separate concerns. A title-only change produces a terminal list snapshot but never touches workspace descriptors. A transition that changes the derived workspace bucket (e.g. idle → working, working → idle, attention cleared) emits both a terminal list snapshot and a server-internal `TerminalWorkspaceContributionChanged` event, which Session consumes to invalidate only the affected workspace.
+
 ### Transitions carry their own history
 
 Each `onChange` delivers both the new snapshot and the `previous` one (`{ state, changedAt }`). The transition flows unchanged up through `TerminalSession.onActivityChange` (as `{ activity, previous }`), the worker protocol's `terminalActivityChange` event, and the manager-level `subscribeTerminalActivity(listener)` stream (`{ terminalId, name, cwd, activity, previous }`).