step-7: add memory middleware (memory_middleware.py, device_ws.py)

MemoryMiddleware class:
- enrich_context(): loads core prefs, associative (top-k), episodic (last-N),
  and proactive hints (above 0.6 confidence) — all decrypted in-memory only
- store_episode(): encrypts and persists interaction summary to memory_episodic
- update_core(): upserts encrypted key/value to memory_core

device_ws.py home_request + popup_request handlers:
- enrich_context() called before orchestrate_v3_stream (memory injected into context)
- store_episode() called after stream completes (non-blocking)

10 unit + integration tests pass; pre-existing test_agents.py failures unrelated.

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

app/api/routes/device_ws.py

@@ -42,6 +42,7 @@ from sqlalchemy import update
 from app.config.settings import settings
 from app.core.agent_runner import trigger_pending_runs
 from app.core.device_manager import device_manager
+from app.core.memory_middleware import MemoryMiddleware
 from app.core.orchestrator import orchestrate_v3_stream
 from app.core.output_formatter import HomeFormatter, PopupFormatter
 from app.core.ws_context import clear_client_executor, set_client_executor
@@ -217,20 +218,29 @@ async def _handle_home_request(
     """Handle a home_request frame — streams HomeFormatter output back on the socket."""
     request_id = frame.get("request_id") or str(uuid4())
     message: str = frame.get("message", "")
+    session_id: str = frame.get("session_id") or str(uuid4())
+
+    # ── Memory: enrich context before LLM call ────────────────────────
+    async with async_session() as db:
+        memory = MemoryMiddleware(db)
+        memory_context = await memory.enrich_context(user_id, message)
+
     context: dict = {
         "conversation_history": frame.get("conversation_history", []),
+        **memory_context,
     }
 
     executor = await _make_ws_executor(websocket, user_id)
     set_client_executor(executor)
+    response_chunks: list[str] = []
     try:
         token_stream = orchestrate_v3_stream(user_id, message, context)
-        # Collect tool_results via the formatter after the stream completes.
-        # We pass an empty list initially; tool_results are populated during
-        # the agent run via ws_context._tool_result_collector (set inside _tool_loop_stream).
         formatter = HomeFormatter(request_id=request_id, tool_results=[])
         async for ws_frame in formatter.format(token_stream):
             await websocket.send_text(ws_frame.model_dump_json())
+            # Collect text chunks to build the full response for episode storage
+            if ws_frame.type == "stream_text":  # type: ignore[union-attr]
+                response_chunks.append(ws_frame.chunk)  # type: ignore[union-attr]
     except Exception as exc:
         logger.error(
             "device_ws: home_request failed user=%s req=%s: %s",
@@ -239,6 +249,13 @@ async def _handle_home_request(
     finally:
         clear_client_executor()
 
+    # ── Memory: store episode after response ──────────────────────────
+    async with async_session() as db:
+        memory = MemoryMiddleware(db)
+        await memory.store_episode(
+            user_id, session_id, message, "".join(response_chunks)
+        )
+
 
 async def _handle_popup_request(
     websocket: WebSocket,
@@ -248,16 +265,26 @@ async def _handle_popup_request(
     """Handle a popup_request frame — streams PopupFormatter output back on the socket."""
     request_id = frame.get("request_id") or str(uuid4())
     message: str = frame.get("message", "")
+    session_id: str = frame.get("session_id") or str(uuid4())
     scope: dict = frame.get("scope", {})
-    context: dict = {"scope": scope}
+
+    # ── Memory: enrich context before LLM call ────────────────────────
+    async with async_session() as db:
+        memory = MemoryMiddleware(db)
+        memory_context = await memory.enrich_context(user_id, message)
+
+    context: dict = {"scope": scope, **memory_context}
 
     executor = await _make_ws_executor(websocket, user_id)
     set_client_executor(executor)
+    response_chunks: list[str] = []
     try:
         token_stream = orchestrate_v3_stream(user_id, message, context)
         formatter = PopupFormatter(request_id=request_id)
         async for ws_frame in formatter.format(token_stream):
             await websocket.send_text(ws_frame.model_dump_json())
+            if ws_frame.type == "stream_text":  # type: ignore[union-attr]
+                response_chunks.append(ws_frame.chunk)  # type: ignore[union-attr]
     except Exception as exc:
         logger.error(
             "device_ws: popup_request failed user=%s req=%s: %s",
@@ -266,6 +293,13 @@ async def _handle_popup_request(
     finally:
         clear_client_executor()
 
+    # ── Memory: store episode after response ──────────────────────────
+    async with async_session() as db:
+        memory = MemoryMiddleware(db)
+        await memory.store_episode(
+            user_id, session_id, message, "".join(response_chunks)
+        )
+
 
 # ── Heartbeat ─────────────────────────────────────────────────────────