debug(punctuation): enhanced lock logging to show which owner blocks punctuation

Added is_locked_by() to StageLocker that returns (start, end, owner).
Logs now show: locked by spelling[59:63] or locked by grammar[73:81]
This helps identify WHY punctuation marks get blocked.

src/app.py

@@ -1156,21 +1156,24 @@ def analyze_text():
                 for d in diffs:
                     # StageLocker: skip diffs that overlap with locked ranges
                     # BUT allow pure punctuation insertions near locked words
-                    if ctx.stage_locker.is_locked(d['start'], d['end']):
+                    lock_info = ctx.stage_locker.is_locked_by(d['start'], d['end'])
+                    if lock_info:
                         import re as _re
                         orig_alpha = _re.sub(r'[^\u0600-\u06FFa-zA-Z]', '', d.get('original', ''))
                         corr_alpha = _re.sub(r'[^\u0600-\u06FFa-zA-Z]', '', d.get('correction', ''))
+                        ls, le, owner = lock_info
                         if orig_alpha != corr_alpha:
                             # Diff changes actual words — block it
                             logger.info(
                                 f"[LOCK] Punctuation blocked on [{d['start']}:{d['end']}] "
-                                f"'{d.get('original','')}' \u2014 locked by previous stage"
+                                f"'{d.get('original','')}' \u2014 locked by {owner}[{ls}:{le}]"
                             )
                             continue
-                        # Arabic text unchanged \u2014 only punctuation added/moved. Allow through.
+                        # Arabic text unchanged — only punctuation added/moved. Allow through.
                         logger.info(
                             f"[LOCK] Punctuation ALLOWED through lock [{d['start']}:{d['end']}] "
-                            f"'{d.get('original','')}' \u2192 '{d.get('correction','')}' \u2014 pure punctuation"
+                            f"'{d.get('original','')}' \u2192 '{d.get('correction','')}' "
+                            f"(locked by {owner}[{ls}:{le}])"
                         )
                     # Punctuation safety layer: reject non-punctuation changes
                     if not validate_punctuation_diff(d):

src/nlp/stage_locker.py

@@ -42,6 +42,13 @@ class StageLocker:
                 return True
         return False
 
+    def is_locked_by(self, start: int, end: int):
+        """Return (locked_start, locked_end, owner) if locked, else None."""
+        for ls, le, owner in self.locked_spans:
+            if start < le and end > ls:
+                return (ls, le, owner)
+        return None
+
     def update_via_mapper(self, mapper) -> None:
         """
         Shift all locked spans to match the new CURRENT_TEXT after mutation.