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>

tests/test_requirements.py

@@ -1,8 +1,10 @@
-import pytest
-from pathlib import Path
 import importlib.metadata
-import tomllib
 import re
+from pathlib import Path
+
+import pytest
+import tomllib
+
 
 def get_root_path():
     return Path(__file__).parent.parent
@@ -16,7 +18,7 @@ def parse_txt_requirements(file_path):
     if not file_path.exists():
         return set()
     packages = set()
-    with open(file_path, "r") as f:
+    with open(file_path) as f:
         for line in f:
             line = line.strip()
             if not line or line.startswith(("#", "-e", "git+", "-r")):
@@ -28,7 +30,7 @@ def parse_toml_section(data, section_type="main"):
     """Extracts full requirement strings from pyproject.toml including optional sections."""
     packages = set()
     project = data.get("project", {})
-    
+
     if section_type == "main":
         deps = project.get("dependencies", [])
     elif section_type == "optional":
@@ -37,7 +39,7 @@ def parse_toml_section(data, section_type="main"):
         deps = project.get("optional-dependencies", {}).get("dev", [])
         if not deps:
             deps = data.get("dependency-groups", {}).get("dev", [])
-            
+
     for req in deps:
         packages.add(_clean_string(req))
     return packages
@@ -54,7 +56,7 @@ def test_dependency_files_integrity():
     # Validate Production Sync (Main + Optionals)
     txt_main = parse_txt_requirements(root / "requirements.txt")
     toml_main = parse_toml_section(toml_data, "main") | parse_toml_section(toml_data, "optional")
-    
+
     assert txt_main == toml_main, (
         f"Production version mismatch!\n"
         f"Only in TXT: {txt_main - toml_main}\n"
@@ -75,10 +77,10 @@ def test_environment_vs_toml():
     root = get_root_path()
     with open(root / "pyproject.toml", "rb") as f:
         data = tomllib.load(f)
-    
+
     all_declared = (
-        parse_toml_section(data, "main") | 
-        parse_toml_section(data, "optional") | 
+        parse_toml_section(data, "main") |
+        parse_toml_section(data, "optional") |
         parse_toml_section(data, "dev")
     )
     _verify_installation(all_declared, "TOML")
@@ -87,7 +89,7 @@ def test_environment_vs_requirements():
     """3. Verifies that installed packages satisfy .txt requirements."""
     root = get_root_path()
     all_txt_deps = (
-        parse_txt_requirements(root / "requirements.txt") | 
+        parse_txt_requirements(root / "requirements.txt") |
         parse_txt_requirements(root / "requirements-dev.txt")
     )
     _verify_installation(all_txt_deps, "requirements.txt")
@@ -95,15 +97,15 @@ def test_environment_vs_requirements():
 def _verify_installation(package_set, source_name):
     """Helper to check if declared versions match installed versions."""
     missing_or_wrong = []
-    
+
     for req in package_set:
         # Split name from version
         parts = re.split(r'==|>=|~=|<=|>|<', req)
         raw_name = parts[0].strip()
-        
+
         # CLEAN EXTRAS: "qrcode[pil]" -> "qrcode"
         clean_name = re.sub(r'\[.*\]', '', raw_name)
-        
+
         try:
             installed_ver = importlib.metadata.version(clean_name)
             if "==" in req: