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/sse.py

@@ -2,12 +2,14 @@
 
 from __future__ import annotations
 
+import contextlib
 import json
 import queue
 import threading
 import time
+from collections.abc import Generator
 from dataclasses import dataclass, field
-from typing import Any, Callable, Generator
+from typing import Any, Callable
 
 
 @dataclass
@@ -29,6 +31,12 @@ def _run_fanout(channel: _QueueFanoutChannel) -> None:
     idle_drain_batch = 512
 
     while True:
+        src = channel.source_queue
+        if src is None:
+            # Source queue was cleared (e.g. during interpreter shutdown).
+            time.sleep(0.5)
+            continue
+
         with channel.lock:
             subscribers = tuple(channel.subscribers)
 
@@ -39,7 +47,7 @@ def _run_fanout(channel: _QueueFanoutChannel) -> None:
             drained = 0
             for _ in range(idle_drain_batch):
                 try:
-                    channel.source_queue.get_nowait()
+                    src.get_nowait()
                     drained += 1
                 except queue.Empty:
                     break
@@ -49,7 +57,7 @@ def _run_fanout(channel: _QueueFanoutChannel) -> None:
             continue
 
         try:
-            msg = channel.source_queue.get(timeout=channel.source_timeout)
+            msg = src.get(timeout=channel.source_timeout)
         except queue.Empty:
             continue
 
@@ -153,10 +161,8 @@ def sse_stream_fanout(
                 msg = subscriber.get(timeout=timeout)
                 last_keepalive = time.time()
                 if on_message and isinstance(msg, dict):
-                    try:
+                    with contextlib.suppress(Exception):
                         on_message(msg)
-                    except Exception:
-                        pass
                 yield format_sse(msg)
             except queue.Empty:
                 now = time.time()
@@ -174,7 +180,7 @@ def sse_stream(
     stop_check: Callable[[], bool] | None = None,
     channel_key: str | None = None,
 ) -> Generator[str, None, None]:
-    """
+    """
     Generate SSE stream from a queue.
 
     Args:
@@ -195,47 +201,47 @@ def sse_stream(
         keepalive_interval=keepalive_interval,
         stop_check=stop_check,
     )
-
-
-def format_sse(data: dict[str, Any] | str, event: str | None = None) -> str:
-    """
-    Format data as SSE message.
-
-    Args:
-        data: Data to send (will be JSON encoded if dict)
-        event: Optional event name
-
-    Returns:
-        SSE formatted string
-    """
-    if isinstance(data, dict):
-        data = json.dumps(data)
-
-    lines = []
-    if event:
-        lines.append(f"event: {event}")
-    lines.append(f"data: {data}")
-    lines.append("")
-    lines.append("")
-
-    return '\n'.join(lines)
-
-
-def clear_queue(q: queue.Queue) -> int:
-    """
-    Clear all items from a queue.
-
-    Args:
-        q: Queue to clear
-
-    Returns:
-        Number of items cleared
-    """
-    count = 0
-    while True:
-        try:
-            q.get_nowait()
-            count += 1
-        except queue.Empty:
-            break
-    return count
+
+
+def format_sse(data: dict[str, Any] | str, event: str | None = None) -> str:
+    """
+    Format data as SSE message.
+
+    Args:
+        data: Data to send (will be JSON encoded if dict)
+        event: Optional event name
+
+    Returns:
+        SSE formatted string
+    """
+    if isinstance(data, dict):
+        data = json.dumps(data)
+
+    lines = []
+    if event:
+        lines.append(f"event: {event}")
+    lines.append(f"data: {data}")
+    lines.append("")
+    lines.append("")
+
+    return '\n'.join(lines)
+
+
+def clear_queue(q: queue.Queue) -> int:
+    """
+    Clear all items from a queue.
+
+    Args:
+        q: Queue to clear
+
+    Returns:
+        Number of items cleared
+    """
+    count = 0
+    while True:
+        try:
+            q.get_nowait()
+            count += 1
+        except queue.Empty:
+            break
+    return count