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>

manual_trading_hub/hub_ai/attachments.py

@@ -1,4 +1,4 @@
-"""中控 AI 聊天附件解析。"""
+"""中控 AI 聊天附件解析."""
 from __future__ import annotations
 
 import base64
@@ -86,11 +86,11 @@ def parse_chat_attachments(raw_files: list[dict[str, Any]]) -> dict[str, Any]:
             meta.append({"name": name, "kind": "text", "mime": mime, "size": size})
             notes.append(f"文档 {name}")
             continue
-        errors.append(f"{name}: 不支持的类型（仅图片或 txt/md/json）")
+        errors.append(f"{name}: 不支持的类型(仅图片或 txt/md/json)")
 
-    attachment_note = "；".join(notes) if notes else ""
+    attachment_note = ";".join(notes) if notes else ""
     if errors:
-        attachment_note = (attachment_note + "；" if attachment_note else "") + "；".join(errors)
+        attachment_note = (attachment_note + ";" if attachment_note else "") + ";".join(errors)
     text_append = "\n\n".join(text_blocks)
     return {
         "images_b64": images_b64,