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/common/static/time_close_ui.js

@@ -1,5 +1,5 @@
 /**
- * 时间平仓 + 整点强制清仓：表单开关 + 持仓/顶栏倒计时。
+ * 时间平仓 + 整点强制清仓:表单开关 + 持仓/顶栏倒计时.
  */
 (function (global) {
   "use strict";