chore: initialize inter-agent signal files

- shared-state.json: joint workspace state + agent statuses
- SESSION.log: human-readable activity log
- Ready for Hermes to write hermes-signal.json

.pi/shared-state.json

@@ -0,0 +1,24 @@
+{
+  "version": "1.0",
+  "lastUpdated": "2026-06-28T05:00:00Z",
+  "workspace": "w1",
+  "agents": {
+    "pi": { "status": "working", "pane": "w1:p1", "currentTask": "PR #1 content seed" },
+    "hermes": { "status": "connected", "clientId": 4, "expectedTask": "Review PR #1" },
+    "opencode": { "status": "blocked", "pane": "w1:p2" },
+    "agy": { "status": "idle", "pane": "w1:p3" }
+  },
+  "schema": {
+    "source": "hermes-existing",
+    "models": ["LearnCourse", "LearnModule", "LearnEnrollment", "LearnModuleProgress"],
+    "verifiedBy": "pi",
+    "verifiedAt": "2026-06-28T04:30:00Z"
+  },
+  "content": {
+    "repo": "gitea:wmj/falahmobile-content",
+    "course": "daily-fiqh-beginner",
+    "modulesReady": 5,
+    "contentFieldPopulated": false,
+    "audioGenerated": false
+  }
+}