Normalize fullwidth punctuation to ASCII across codebase.

Add scripts/normalize_ambiguous_unicode.py; fix corrupted patch_instance_theme_templates.py. Preserves curly quotes in string literals; removes Git homoglyph warnings on .env.example.

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/instance/runtime_config_lib.py

@@ -1,4 +1,4 @@
-"""env 运行时覆盖：热生效项优先读 SQLite，再回退 os.environ。"""
+"""env 运行时覆盖:热生效项优先读 SQLite,再回退 os.environ."""
 from __future__ import annotations
 
 import os
@@ -42,7 +42,7 @@ def set_config_overrides(get_db: Callable, mapping: dict[str, str]) -> None:
 
 
 def apply_env_reload(env_path: str, get_db: Callable, changed_keys: list[str], groups: list[dict]) -> dict[str, bool]:
-    """写盘后同步 os.environ，并将可热生效项写入 runtime 覆盖。"""
+    """写盘后同步 os.environ,并将可热生效项写入 runtime 覆盖."""
     load_env_file_into_environ(env_path)
     hot: dict[str, str] = {}
     field_map = {}