v2.26.0: fix SSE fanout crash and branded logo FOUC

- Fix SSE fanout thread AttributeError when source queue is None during
  interpreter shutdown by snapshotting to local variable with null guard
- Fix branded "i" logo rendering oversized on first page load (FOUC) by
  adding inline width/height to SVG elements across 10 templates
- Bump version to 2.26.0 in config.py, pyproject.toml, and CHANGELOG.md

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

utils/__init__.py

@@ -1,43 +1,43 @@
 # Utility modules for INTERCEPT
-from .dependencies import check_tool, check_all_dependencies, TOOL_DEPENDENCIES
-from .process import (
-    cleanup_stale_processes,
-    is_valid_mac,
-    is_valid_channel,
-    detect_devices,
-    safe_terminate,
-    register_process,
-    unregister_process,
-    cleanup_all_processes,
-)
+from .cleanup import CleanupManager, DataStore, cleanup_dict, cleanup_manager
+from .dependencies import TOOL_DEPENDENCIES, check_all_dependencies, check_tool
 from .logging import (
-    get_logger,
+    adsb_logger,
     app_logger,
+    bluetooth_logger,
+    get_logger,
     pager_logger,
+    satellite_logger,
     sensor_logger,
     wifi_logger,
-    bluetooth_logger,
-    adsb_logger,
-    satellite_logger,
 )
+from .process import (
+    cleanup_all_processes,
+    cleanup_stale_processes,
+    detect_devices,
+    is_valid_channel,
+    is_valid_mac,
+    register_process,
+    safe_terminate,
+    unregister_process,
+)
+from .sse import clear_queue, format_sse, sse_stream
 from .validation import (
     escape_html,
+    sanitize_callsign,
+    sanitize_device_name,
+    sanitize_ssid,
+    validate_device_index,
+    validate_elevation,
+    validate_frequency,
+    validate_gain,
+    validate_hours,
     validate_latitude,
     validate_longitude,
-    validate_frequency,
-    validate_device_index,
-    validate_rtl_tcp_host,
-    validate_rtl_tcp_port,
-    validate_gain,
-    validate_ppm,
-    validate_hours,
-    validate_elevation,
-    validate_wifi_channel,
     validate_mac_address,
     validate_positive_int,
-    sanitize_callsign,
-    sanitize_ssid,
-    sanitize_device_name,
+    validate_ppm,
+    validate_rtl_tcp_host,
+    validate_rtl_tcp_port,
+    validate_wifi_channel,
 )
-from .sse import sse_stream, format_sse, clear_queue
-from .cleanup import DataStore, CleanupManager, cleanup_manager, cleanup_dict