fix: resolve all CI test failures — lazy tkinter, mock network calls

- Lazy-import tkinter in screen_overlay.py (TYPE_CHECKING + runtime
  import) so the module loads on headless Linux CI without libtk8.6
- Fix test_wled_client.py: mock all HTTP endpoints with respx (info,
  cfg, state) instead of hitting real network
- Fix test_calibration.py: assert numpy array shape instead of tuple
- Fix test_processor_manager.py: update to current API (async
  remove_device, dict settings, no update_calibration)
- Fix test_screen_capture.py: get_edge_segments allows more segments
  than pixels

341 tests passing, 0 failures.

server/tests/test_wled_client.py

@@ -27,6 +27,20 @@ def mock_wled_info():
     }
 
 
+@pytest.fixture
+def mock_wled_cfg():
+    """Provide mock WLED config response (needed by get_info)."""
+    return {
+        "hw": {
+            "led": {
+                "ins": [
+                    {"start": 0, "len": 150, "order": 1, "pin": [2], "type": 22}
+                ]
+            }
+        }
+    }
+
+
 @pytest.fixture
 def mock_wled_state():
     """Provide mock WLED state response."""
@@ -37,13 +51,28 @@ def mock_wled_state():
     }
 
 
-@pytest.mark.asyncio
-@respx.mock
-async def test_wled_client_connect(wled_url, mock_wled_info):
-    """Test connecting to WLED device."""
+def _mock_connect_endpoints(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
+    """Set up respx mocks for all endpoints hit during connect().
+
+    connect() calls get_info() which hits /json/info + /json/cfg,
+    then snapshot_device_state() which hits /json/state.
+    """
     respx.get(f"{wled_url}/json/info").mock(
         return_value=Response(200, json=mock_wled_info)
     )
+    respx.get(f"{wled_url}/json/cfg").mock(
+        return_value=Response(200, json=mock_wled_cfg)
+    )
+    respx.get(f"{wled_url}/json/state").mock(
+        return_value=Response(200, json=mock_wled_state)
+    )
+
+
+@pytest.mark.asyncio
+@respx.mock
+async def test_wled_client_connect(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
+    """Test connecting to WLED device."""
+    _mock_connect_endpoints(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state)
 
     client = WLEDClient(wled_url)
     success = await client.connect()
@@ -72,11 +101,9 @@ async def test_wled_client_connect_failure(wled_url):
 
 @pytest.mark.asyncio
 @respx.mock
-async def test_get_info(wled_url, mock_wled_info):
+async def test_get_info(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
     """Test getting device info."""
-    respx.get(f"{wled_url}/json/info").mock(
-        return_value=Response(200, json=mock_wled_info)
-    )
+    _mock_connect_endpoints(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state)
 
     async with WLEDClient(wled_url) as client:
         info = await client.get_info()
@@ -90,14 +117,9 @@ async def test_get_info(wled_url, mock_wled_info):
 
 @pytest.mark.asyncio
 @respx.mock
-async def test_get_state(wled_url, mock_wled_info, mock_wled_state):
+async def test_get_state(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
     """Test getting device state."""
-    respx.get(f"{wled_url}/json/info").mock(
-        return_value=Response(200, json=mock_wled_info)
-    )
-    respx.get(f"{wled_url}/json/state").mock(
-        return_value=Response(200, json=mock_wled_state)
-    )
+    _mock_connect_endpoints(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state)
 
     async with WLEDClient(wled_url) as client:
         state = await client.get_state()
@@ -108,11 +130,9 @@ async def test_get_state(wled_url, mock_wled_info, mock_wled_state):
 
 @pytest.mark.asyncio
 @respx.mock
-async def test_send_pixels(wled_url, mock_wled_info):
+async def test_send_pixels(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
     """Test sending pixel data."""
-    respx.get(f"{wled_url}/json/info").mock(
-        return_value=Response(200, json=mock_wled_info)
-    )
+    _mock_connect_endpoints(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state)
     respx.post(f"{wled_url}/json/state").mock(
         return_value=Response(200, json={"success": True})
     )
@@ -130,11 +150,9 @@ async def test_send_pixels(wled_url, mock_wled_info):
 
 @pytest.mark.asyncio
 @respx.mock
-async def test_send_pixels_invalid_values(wled_url, mock_wled_info):
+async def test_send_pixels_invalid_values(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
     """Test sending invalid pixel values."""
-    respx.get(f"{wled_url}/json/info").mock(
-        return_value=Response(200, json=mock_wled_info)
-    )
+    _mock_connect_endpoints(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state)
 
     async with WLEDClient(wled_url) as client:
         # Invalid RGB value
@@ -152,11 +170,9 @@ async def test_send_pixels_invalid_values(wled_url, mock_wled_info):
 
 @pytest.mark.asyncio
 @respx.mock
-async def test_set_power(wled_url, mock_wled_info):
+async def test_set_power(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
     """Test turning device on/off."""
-    respx.get(f"{wled_url}/json/info").mock(
-        return_value=Response(200, json=mock_wled_info)
-    )
+    _mock_connect_endpoints(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state)
     respx.post(f"{wled_url}/json/state").mock(
         return_value=Response(200, json={"success": True})
     )
@@ -173,11 +189,9 @@ async def test_set_power(wled_url, mock_wled_info):
 
 @pytest.mark.asyncio
 @respx.mock
-async def test_set_brightness(wled_url, mock_wled_info):
+async def test_set_brightness(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
     """Test setting brightness."""
-    respx.get(f"{wled_url}/json/info").mock(
-        return_value=Response(200, json=mock_wled_info)
-    )
+    _mock_connect_endpoints(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state)
     respx.post(f"{wled_url}/json/state").mock(
         return_value=Response(200, json={"success": True})
     )
@@ -193,11 +207,9 @@ async def test_set_brightness(wled_url, mock_wled_info):
 
 @pytest.mark.asyncio
 @respx.mock
-async def test_test_connection(wled_url, mock_wled_info):
+async def test_test_connection(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
     """Test connection testing."""
-    respx.get(f"{wled_url}/json/info").mock(
-        return_value=Response(200, json=mock_wled_info)
-    )
+    _mock_connect_endpoints(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state)
 
     async with WLEDClient(wled_url) as client:
         success = await client.test_connection()
@@ -206,36 +218,40 @@ async def test_test_connection(wled_url, mock_wled_info):
 
 @pytest.mark.asyncio
 @respx.mock
-async def test_retry_logic(wled_url, mock_wled_info):
+async def test_retry_logic(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
     """Test retry logic on failures."""
-    # Mock to fail twice, then succeed
-    call_count = 0
+    # Mock to fail twice, then succeed on /json/info
+    info_call_count = 0
 
-    def mock_response(request):
-        nonlocal call_count
-        call_count += 1
-        if call_count < 3:
+    def mock_info_response(request):
+        nonlocal info_call_count
+        info_call_count += 1
+        if info_call_count < 3:
             return Response(500, text="Error")
         return Response(200, json=mock_wled_info)
 
-    respx.get(f"{wled_url}/json/info").mock(side_effect=mock_response)
+    respx.get(f"{wled_url}/json/info").mock(side_effect=mock_info_response)
+    respx.get(f"{wled_url}/json/cfg").mock(
+        return_value=Response(200, json=mock_wled_cfg)
+    )
+    respx.get(f"{wled_url}/json/state").mock(
+        return_value=Response(200, json=mock_wled_state)
+    )
 
     client = WLEDClient(wled_url, retry_attempts=3, retry_delay=0.1)
     success = await client.connect()
 
     assert success is True
-    assert call_count == 3  # Failed 2 times, succeeded on 3rd
+    assert info_call_count == 3  # Failed 2 times, succeeded on 3rd
 
     await client.close()
 
 
 @pytest.mark.asyncio
 @respx.mock
-async def test_context_manager(wled_url, mock_wled_info):
+async def test_context_manager(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state):
     """Test async context manager usage."""
-    respx.get(f"{wled_url}/json/info").mock(
-        return_value=Response(200, json=mock_wled_info)
-    )
+    _mock_connect_endpoints(wled_url, mock_wled_info, mock_wled_cfg, mock_wled_state)
 
     async with WLEDClient(wled_url) as client:
         assert client.is_connected is True