兩支閘改看「指令要動的那個 repo」，不看 hook 自己的環境／cwd（inkstone/ISEP#109 → comment 6629）

① line-needs-own-worktree.sh：出路 `WORKTREE_OK=1 git -C … checkout …` 改認指令字串裡的字面前綴
   （舊版讀 hook 自己的環境變數，PreToolUse hook 跟指令不是同一個行程，那行永遠走不通）。
   判準是位置不是字：前綴必須掛在會移動 HEAD 的那條 git 指令上。
   lib/checkout_target_dir.py 加 `--escape NAME=1`；push_target_dir._classify 在 strip_env 時
   把前綴留在 verb 事件裡（find_push_target 行為不變，主線閘 10＋19 條照綠）。
② github-contact-guard.sh：remote 名在「這條指令實際會推的那個 repo」裡解（沿用 lib/push_target_dir.py
   解 cd 鏈／-C／子殼），解不出來才退回 cwd。判準仍是 remote URL 主機，不是「有 -C 就放行」。

測試：A24 59→69（E 群把閘印的那一行原樣餵回去；舊閘 3 條紅）、
      A39 14→26（payload 帶 cwd、cwd≠目標 repo；舊閘 7 條紅＝4 誤攔＋3 漏擋）。
盤點表：61 支／85 條，改判準不加閘，當場數的。
版本：待總管定版。

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0178ef1fGw3XeZtpN7LaZrm4

hooks/lib/push_target_dir.py

@@ -91,21 +91,31 @@ def _classify(tokens, verbs=("push",), strip_env=False):
     stays deliberately loose here (the verb may sit anywhere after `git`) --
     callers re-walk the returned token list to confirm command position, so
     a false positive at this layer costs nothing."""
+    body = tokens
     if strip_env:
         # `FOO=1 git checkout …` -- an env prefix doesn't change which command
         # runs. Opt-in so find_push_target's behaviour stays byte-identical;
         # checkout_target_dir.py turns it on (its predecessor stripped these,
         # and dropping that would have been a silent regression -- caught by
         # the worktree gate's own case ㉒).
+        #
+        # 2026-09-07 (inkstone/ISEP#109 -> comment 6587): the prefix is skipped
+        # for *classifying* the statement, but the "verb" event hands back the
+        # full token list, prefix included. The worktree gate's escape hatch is
+        # exactly that prefix (`WORKTREE_OK=1 git checkout …`), and a PreToolUse
+        # hook can only see it in the command string -- it never reaches the
+        # hook's own environment. Dropping it here made the printed way out
+        # unwalkable. Callers that don't care simply skip leading NAME=value
+        # tokens themselves (checkout_target_dir._moves_head does).
         i = 0
         while i < len(tokens) and _ENV_ASSIGN.match(tokens[i]):
             i += 1
-        tokens = tokens[i:]
-    if not tokens:
+        body = tokens[i:]
+    if not body:
         return ("other", None)
-    if tokens[0] == "cd" and len(tokens) > 1:
-        return ("cd", tokens[1])
-    if tokens[0] == "git" and any(v in tokens[1:] for v in verbs):
+    if body[0] == "cd" and len(body) > 1:
+        return ("cd", body[1])
+    if body[0] == "git" and any(v in body[1:] for v in verbs):
         return ("verb", tokens)
     return ("other", None)