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/tscm/baseline.py

@@ -9,12 +9,10 @@ from __future__ import annotations
 
 import logging
 from datetime import datetime
-from typing import Any
 
 from utils.database import (
     create_tscm_baseline,
     get_active_tscm_baseline,
-    get_tscm_baseline,
     update_tscm_baseline,
 )
 
@@ -107,7 +105,6 @@ class BaselineRecorder:
             f"{summary['bt_count']} BT, {summary['rf_count']} RF"
         )
 
-        baseline_id = self.current_baseline_id
         self.current_baseline_id = None
 
         return summary