chore(config): add git-lock-guard PreToolUse hook

Clears stale .git/index.lock files before git write commands.
Claude Code's internal git status polling leaves orphan locks
(anthropics/claude-code#11005) that block add/commit/merge/push.

The hook checks lsof/fuser before removing — only stale locks are
cleared, never locks held by live processes. Read-only git commands
are skipped entirely.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.claude/hooks/git-lock-guard.sh

@@ -0,0 +1,63 @@
+#!/usr/bin/env bash
+# git-lock-guard: PreToolUse hook that clears stale git index.lock files
+# before git write operations.
+#
+# Claude Code's internal git status polling creates stale lock files that
+# persist after the process exits (anthropics/claude-code#11005). This hook
+# detects and removes them before LLM-initiated git commands run.
+#
+# Only acts on git write commands (add, commit, merge, push, etc.).
+# Read-only commands (status, log, diff, show) are skipped.
+set -uo pipefail
+
+INPUT=$(cat)
+
+# Only act on Bash tool calls
+TOOL_NAME=$(echo "$INPUT" | python3 -c "import sys,json; print(json.load(sys.stdin).get('tool_name',''))" 2>/dev/null)
+[ "$TOOL_NAME" = "Bash" ] || exit 0
+
+COMMAND=$(echo "$INPUT" | python3 -c "import sys,json; print(json.load(sys.stdin).get('tool_input',{}).get('command',''))" 2>/dev/null)
+
+# Only act on git write commands — skip read-only operations
+case "$COMMAND" in
+  git\ add*|git\ commit*|git\ merge*|git\ push*|git\ pull*|\
+  git\ checkout*|git\ stash*|git\ rebase*|git\ reset*|\
+  git\ cherry-pick*|git\ rm*|git\ mv*|git\ fetch*)
+    ;;
+  *)
+    exit 0
+    ;;
+esac
+
+# Resolve the git directory for the current working directory
+CWD=$(echo "$INPUT" | python3 -c "import sys,json; print(json.load(sys.stdin).get('cwd',''))" 2>/dev/null)
+[ -n "$CWD" ] || exit 0
+
+# Find the .git directory (handles both regular repos and worktrees)
+GIT_DIR=$(git -C "$CWD" rev-parse --git-dir 2>/dev/null) || exit 0
+
+# For worktrees, also check the common git dir (shared index operations)
+GIT_COMMON_DIR=$(git -C "$CWD" rev-parse --git-common-dir 2>/dev/null) || GIT_COMMON_DIR="$GIT_DIR"
+
+for DIR in "$GIT_DIR" "$GIT_COMMON_DIR"; do
+  LOCK="$DIR/index.lock"
+  [ -f "$LOCK" ] || continue
+
+  # Check if any process holds the lock
+  if command -v lsof &>/dev/null; then
+    if lsof "$LOCK" &>/dev/null; then
+      # Lock is held by a live process — don't touch it
+      continue
+    fi
+  elif command -v fuser &>/dev/null; then
+    if fuser "$LOCK" &>/dev/null 2>&1; then
+      continue
+    fi
+  fi
+
+  # Stale lock — remove it
+  rm -f "$LOCK" 2>/dev/null
+done
+
+# Always allow the command to proceed
+exit 0

.claude/settings.json

@@ -80,5 +80,19 @@
       "Bash(git clean -f *)",
       "Bash(rm -rf *)"
     ]
+  },
+  "hooks": {
+    "PreToolUse": [
+      {
+        "matcher": "Bash",
+        "hooks": [
+          {
+            "type": "command",
+            "command": ".claude/hooks/git-lock-guard.sh",
+            "timeout": 5
+          }
+        ]
+      }
+    ]
   }
 }