rescue: WS heartbeat ping + commitment tracking from stale PRs (#415)

## What
Manually integrated unique code from two stale PRs that were **not** superseded by merged work.

### PR #399 (kimi/issue-362) — WebSocket heartbeat ping
- 15-second ping loop detects dead iPad/Safari connections
- `_heartbeat()` coroutine launched as background task per WS client
- `ping_task` properly cancelled on disconnect

### PR #408 (kimi/issue-322) — Conversation commitment tracking
- Regex extraction of commitments from Timmy replies (`I'll` / `I will` / `Let me`)
- `_record_commitments()` stores with dedup + cap at 10
- `_tick_commitments()` increments message counter per commitment
- `_build_commitment_context()` surfaces overdue commitments as grounding context
- Wired into `_bark_and_broadcast()` and `_generate_bark()`
- Public API: `get_commitments()`, `close_commitment()`, `reset_commitments()`

### Tests
22 new tests covering both features: extraction, recording, dedup, caps, tick/context, integration, heartbeat ping, dead connection handling.

---
This PR rescues unique code from stale PRs #399 and #408. The other two stale PRs (#402, #411) were already superseded by merged work and should be closed.

Co-authored-by: Perplexity Computer <perplexity@tower.dev>
Reviewed-on: http://localhost:3000/rockachopa/Timmy-time-dashboard/pulls/415
Co-authored-by: Perplexity Computer <perplexity@tower.local>
Co-committed-by: Perplexity Computer <perplexity@tower.local>

tests/dashboard/test_world_api.py

@@ -7,19 +7,31 @@ from unittest.mock import AsyncMock, MagicMock, patch
 
 import pytest
 
+import asyncio
+
 from dashboard.routes.world import (
     _GROUND_TTL,
+    _REMIND_AFTER,
     _STALE_THRESHOLD,
     _bark_and_broadcast,
     _broadcast,
+    _build_commitment_context,
     _build_world_state,
+    _commitments,
     _conversation,
+    _extract_commitments,
     _generate_bark,
     _handle_client_message,
+    _heartbeat,
     _log_bark_failure,
     _read_presence_file,
+    _record_commitments,
     _refresh_ground,
+    _tick_commitments,
     broadcast_world_state,
+    close_commitment,
+    get_commitments,
+    reset_commitments,
     reset_conversation_ground,
 )
 
@@ -506,3 +518,206 @@ class TestConversationGrounding:
         finally:
             _ws_clients.clear()
             _conversation.clear()
+
+
+# ---------------------------------------------------------------------------
+# Conversation grounding — commitment tracking (rescued from PR #408)
+# ---------------------------------------------------------------------------
+
+
+@pytest.fixture(autouse=False)
+def _clean_commitments():
+    """Reset commitments before and after each commitment test."""
+    reset_commitments()
+    yield
+    reset_commitments()
+
+
+class TestExtractCommitments:
+    def test_extracts_ill_pattern(self):
+        text = "I'll draft the skeleton ticket in 30 minutes."
+        result = _extract_commitments(text)
+        assert len(result) == 1
+        assert "draft the skeleton ticket" in result[0]
+
+    def test_extracts_i_will_pattern(self):
+        result = _extract_commitments("I will review that PR tomorrow.")
+        assert len(result) == 1
+        assert "review that PR tomorrow" in result[0]
+
+    def test_extracts_let_me_pattern(self):
+        result = _extract_commitments("Let me write up a summary for you.")
+        assert len(result) == 1
+        assert "write up a summary" in result[0]
+
+    def test_skips_short_matches(self):
+        result = _extract_commitments("I'll do it.")
+        # "do it" is 5 chars — should be skipped (needs > 5)
+        assert result == []
+
+    def test_no_commitments_in_normal_text(self):
+        result = _extract_commitments("The weather is nice today.")
+        assert result == []
+
+    def test_truncates_long_commitments(self):
+        long_phrase = "a" * 200
+        result = _extract_commitments(f"I'll {long_phrase}.")
+        assert len(result) == 1
+        assert len(result[0]) == 120
+
+
+class TestRecordCommitments:
+    def test_records_new_commitment(self, _clean_commitments):
+        _record_commitments("I'll draft the ticket now.")
+        assert len(get_commitments()) == 1
+        assert get_commitments()[0]["messages_since"] == 0
+
+    def test_avoids_duplicate_commitments(self, _clean_commitments):
+        _record_commitments("I'll draft the ticket now.")
+        _record_commitments("I'll draft the ticket now.")
+        assert len(get_commitments()) == 1
+
+    def test_caps_at_max(self, _clean_commitments):
+        from dashboard.routes.world import _MAX_COMMITMENTS
+
+        for i in range(_MAX_COMMITMENTS + 3):
+            _record_commitments(f"I'll handle commitment number {i} right away.")
+        assert len(get_commitments()) <= _MAX_COMMITMENTS
+
+
+class TestTickAndContext:
+    def test_tick_increments_messages_since(self, _clean_commitments):
+        _commitments.append({"text": "write the docs", "created_at": 0, "messages_since": 0})
+        _tick_commitments()
+        _tick_commitments()
+        assert _commitments[0]["messages_since"] == 2
+
+    def test_context_empty_when_no_overdue(self, _clean_commitments):
+        _commitments.append({"text": "write the docs", "created_at": 0, "messages_since": 0})
+        assert _build_commitment_context() == ""
+
+    def test_context_surfaces_overdue_commitments(self, _clean_commitments):
+        _commitments.append(
+            {
+                "text": "draft the skeleton ticket",
+                "created_at": 0,
+                "messages_since": _REMIND_AFTER,
+            }
+        )
+        ctx = _build_commitment_context()
+        assert "draft the skeleton ticket" in ctx
+        assert "Open commitments" in ctx
+
+    def test_context_only_includes_overdue(self, _clean_commitments):
+        _commitments.append({"text": "recent thing", "created_at": 0, "messages_since": 1})
+        _commitments.append(
+            {
+                "text": "old thing",
+                "created_at": 0,
+                "messages_since": _REMIND_AFTER,
+            }
+        )
+        ctx = _build_commitment_context()
+        assert "old thing" in ctx
+        assert "recent thing" not in ctx
+
+
+class TestCloseCommitment:
+    def test_close_valid_index(self, _clean_commitments):
+        _commitments.append({"text": "write the docs", "created_at": 0, "messages_since": 0})
+        assert close_commitment(0) is True
+        assert len(get_commitments()) == 0
+
+    def test_close_invalid_index(self, _clean_commitments):
+        assert close_commitment(99) is False
+
+
+class TestGroundingIntegration:
+    @pytest.mark.asyncio
+    async def test_bark_records_commitments_from_reply(self, _clean_commitments):
+        from dashboard.routes.world import _ws_clients
+
+        ws = AsyncMock()
+        _ws_clients.append(ws)
+        _conversation.clear()
+        try:
+            with patch(
+                "timmy.session.chat",
+                new_callable=AsyncMock,
+                return_value="I'll draft the ticket for you!",
+            ):
+                await _bark_and_broadcast("Can you help?")
+
+            assert len(get_commitments()) == 1
+            assert "draft the ticket" in get_commitments()[0]["text"]
+        finally:
+            _ws_clients.clear()
+            _conversation.clear()
+
+    @pytest.mark.asyncio
+    async def test_bark_prepends_context_after_n_messages(self, _clean_commitments):
+        """After _REMIND_AFTER messages, commitment context is prepended."""
+        _commitments.append(
+            {
+                "text": "draft the skeleton ticket",
+                "created_at": 0,
+                "messages_since": _REMIND_AFTER - 1,
+            }
+        )
+
+        with patch(
+            "timmy.session.chat",
+            new_callable=AsyncMock,
+            return_value="Sure thing!",
+        ) as mock_chat:
+            # This tick will push messages_since to _REMIND_AFTER
+            await _generate_bark("Any updates?")
+            # _generate_bark doesn't tick — _bark_and_broadcast does.
+            # But we pre-set messages_since to _REMIND_AFTER - 1,
+            # so we need to tick once to make it overdue.
+            _tick_commitments()
+            await _generate_bark("Any updates?")
+
+            # Second call should have context prepended
+            last_call = mock_chat.call_args_list[-1]
+            sent_text = last_call[0][0]
+            assert "draft the skeleton ticket" in sent_text
+            assert "Open commitments" in sent_text
+
+
+# ---------------------------------------------------------------------------
+# WebSocket heartbeat ping (rescued from PR #399)
+# ---------------------------------------------------------------------------
+
+
+@pytest.mark.asyncio
+async def test_heartbeat_sends_ping():
+    """Heartbeat sends a ping JSON frame after the interval elapses."""
+    ws = AsyncMock()
+
+    with patch("dashboard.routes.world.asyncio.sleep", new_callable=AsyncMock) as mock_sleep:
+        # Let the first sleep complete, then raise to exit the loop
+        call_count = 0
+
+        async def sleep_side_effect(_interval):
+            nonlocal call_count
+            call_count += 1
+            if call_count > 1:
+                raise ConnectionError("stop")
+
+        mock_sleep.side_effect = sleep_side_effect
+        await _heartbeat(ws)
+
+    ws.send_text.assert_called_once()
+    msg = json.loads(ws.send_text.call_args[0][0])
+    assert msg["type"] == "ping"
+
+
+@pytest.mark.asyncio
+async def test_heartbeat_exits_on_dead_connection():
+    """Heartbeat exits cleanly when the WebSocket is dead."""
+    ws = AsyncMock()
+    ws.send_text.side_effect = ConnectionError("gone")
+
+    with patch("dashboard.routes.world.asyncio.sleep", new_callable=AsyncMock):
+        await _heartbeat(ws)  # should not raise