feat: wire mobile app to real Timmy backend via JSON REST API (#73)

Add /api/chat, /api/upload, and /api/chat/history endpoints to the
FastAPI dashboard so the Expo mobile app talks directly to Timmy's
brain (Ollama) instead of a non-existent Node.js server.

Backend:
- New src/dashboard/routes/chat_api.py with 4 endpoints
- Mount /uploads/ for serving chat attachments
- Same context injection and session management as HTMX chat

Mobile app fixes:
- Point API base URL at port 8000 (FastAPI) instead of 3000
- Create lib/_core/theme.ts (was referenced but never created)
- Fix shared/types.ts (remove broken drizzle/errors re-exports)
- Remove broken server/chat.ts and 1,235-line template README
- Clean package.json (remove express, mysql2, drizzle, tRPC deps)
- Remove debug console.log from theme-provider

Tests: 13 new tests covering all API endpoints (all passing).

https://claude.ai/code/session_01XqErDoh2rVsPY8oTj21Lz2

Co-authored-by: Claude <noreply@anthropic.com>

tests/dashboard/test_chat_api.py

@@ -0,0 +1,177 @@
+"""Tests for the JSON chat API (/api/chat, /api/upload, /api/chat/history)."""
+
+import io
+from unittest.mock import patch
+
+
+# ── POST /api/chat ────────────────────────────────────────────────────────────
+
+
+def test_api_chat_success(client):
+    with patch("dashboard.routes.chat_api.timmy_chat", return_value="Hello from Timmy."):
+        response = client.post(
+            "/api/chat",
+            json={"messages": [{"role": "user", "content": "hello"}]},
+        )
+
+    assert response.status_code == 200
+    data = response.json()
+    assert data["reply"] == "Hello from Timmy."
+    assert "timestamp" in data
+
+
+def test_api_chat_multimodal_content(client):
+    """Multimodal content arrays should extract text parts."""
+    with patch("dashboard.routes.chat_api.timmy_chat", return_value="I see an image."):
+        response = client.post(
+            "/api/chat",
+            json={
+                "messages": [
+                    {
+                        "role": "user",
+                        "content": [
+                            {"type": "text", "text": "What is this?"},
+                            {"type": "image_url", "image_url": {"url": "/uploads/test.jpg"}},
+                        ],
+                    }
+                ]
+            },
+        )
+
+    assert response.status_code == 200
+    assert response.json()["reply"] == "I see an image."
+
+
+def test_api_chat_empty_messages(client):
+    response = client.post("/api/chat", json={"messages": []})
+    assert response.status_code == 400
+    assert "error" in response.json()
+
+
+def test_api_chat_missing_messages(client):
+    response = client.post("/api/chat", json={"foo": "bar"})
+    assert response.status_code == 400
+    assert "messages" in response.json()["error"]
+
+
+def test_api_chat_no_user_message(client):
+    response = client.post(
+        "/api/chat",
+        json={"messages": [{"role": "assistant", "content": "hi"}]},
+    )
+    assert response.status_code == 400
+    assert "No user message" in response.json()["error"]
+
+
+def test_api_chat_ollama_offline(client):
+    with patch(
+        "dashboard.routes.chat_api.timmy_chat",
+        side_effect=ConnectionError("Ollama unreachable"),
+    ):
+        response = client.post(
+            "/api/chat",
+            json={"messages": [{"role": "user", "content": "hello"}]},
+        )
+
+    assert response.status_code == 503
+    data = response.json()
+    assert "offline" in data["error"].lower() or "unreachable" in data["error"].lower()
+
+
+def test_api_chat_logs_to_message_log(client):
+    from dashboard.store import message_log
+
+    with patch("dashboard.routes.chat_api.timmy_chat", return_value="Reply."):
+        client.post(
+            "/api/chat",
+            json={"messages": [{"role": "user", "content": "test msg"}]},
+        )
+
+    entries = message_log.all()
+    assert len(entries) == 2
+    assert entries[0].role == "user"
+    assert entries[0].content == "test msg"
+    assert entries[1].role == "agent"
+    assert entries[1].content == "Reply."
+
+
+def test_api_chat_invalid_json(client):
+    response = client.post(
+        "/api/chat",
+        content=b"not json",
+        headers={"content-type": "application/json"},
+    )
+    assert response.status_code == 400
+
+
+# ── POST /api/upload ──────────────────────────────────────────────────────────
+
+
+def test_api_upload_file(client, tmp_path):
+    with patch("dashboard.routes.chat_api._UPLOAD_DIR", str(tmp_path)):
+        response = client.post(
+            "/api/upload",
+            files={"file": ("test.txt", io.BytesIO(b"hello world"), "text/plain")},
+        )
+
+    assert response.status_code == 200
+    data = response.json()
+    assert data["fileName"] == "test.txt"
+    assert data["mimeType"] == "text/plain"
+    assert "/uploads/" in data["url"]
+
+
+def test_api_upload_image(client, tmp_path):
+    # 1x1 red PNG
+    png = (
+        b"\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x00\x01"
+        b"\x00\x00\x00\x01\x08\x02\x00\x00\x00\x90wS\xde\x00"
+    )
+    with patch("dashboard.routes.chat_api._UPLOAD_DIR", str(tmp_path)):
+        response = client.post(
+            "/api/upload",
+            files={"file": ("photo.png", io.BytesIO(png), "image/png")},
+        )
+
+    assert response.status_code == 200
+    data = response.json()
+    assert data["fileName"] == "photo.png"
+    assert data["mimeType"] == "image/png"
+
+
+# ── GET /api/chat/history ────────────────────────────────────────────────────
+
+
+def test_api_chat_history_empty(client):
+    response = client.get("/api/chat/history")
+    assert response.status_code == 200
+    assert response.json()["messages"] == []
+
+
+def test_api_chat_history_after_chat(client):
+    with patch("dashboard.routes.chat_api.timmy_chat", return_value="Hi!"):
+        client.post(
+            "/api/chat",
+            json={"messages": [{"role": "user", "content": "hello"}]},
+        )
+
+    response = client.get("/api/chat/history")
+    assert response.status_code == 200
+    msgs = response.json()["messages"]
+    assert len(msgs) == 2
+    assert msgs[0]["role"] == "user"
+    assert msgs[1]["role"] == "agent"
+
+
+# ── DELETE /api/chat/history ──────────────────────────────────────────────────
+
+
+def test_api_clear_history(client):
+    from dashboard.store import message_log
+
+    message_log.append(role="user", content="old", timestamp="00:00:00")
+
+    response = client.delete("/api/chat/history")
+    assert response.status_code == 200
+    assert response.json()["success"] is True
+    assert len(message_log) == 0