chore(claude): add spec-drift pre-commit reminder hook

Adds .claude/hooks/pre-commit-spec.sh which blocks every commit attempt
and prompts the agent to deep-read specs/ and decide whether any spec
needs updating for the staged change.

Mandatory touch-flag escape (/tmp/claude-spec-confirmed-<session-id>)
prevents the hook from looping forever — the agent must consciously
acknowledge 'specs are still accurate' once per commit attempt.

Wired into .claude/settings.json as the first PreToolUse hook for
'git commit', running before the existing format/lint/test hook.

Author: delexw

.claude/hooks/pre-commit-spec.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+# Pre-commit hook: spec reminder.
+# Always blocks the first commit attempt and tells the agent to reconsider
+# whether specs/ needs updating. The touch-flag escape is the only way out,
+# so the agent must consciously confirm "specs are aligned" each commit.
+# Without the flag the hook would loop forever.
+
+set -uo pipefail
+
+HOOK_INPUT=$(cat)
+SESSION_ID=$(printf '%s' "$HOOK_INPUT" | jq -r '.session_id // ""')
+FLAG_FILE="/tmp/claude-spec-confirmed${SESSION_ID:+-$SESSION_ID}"
+
+# Acknowledged → consume flag and pass.
+if [ -f "$FLAG_FILE" ]; then
+  rm -f "$FLAG_FILE"
+  exit 0
+fi
+
+REASON="Before committing: deep-read specs/ and reconsider whether any spec needs updating for this change.\n\n"
+REASON+="  • If a spec is now WRONG → update it, then git add specs/<file>, then retry.\n"
+REASON+="  • If a changed area has NO spec → add a new specs/NN-<topic>.md or extend an existing spec, then git add specs/<file>, then retry.\n"
+REASON+="  • If specs are still accurate AND coverage is intentional → in a SEPARATE Bash tool call run:\n      touch $FLAG_FILE\n    then retry the commit.\n"
+REASON+="\nDeep-read means open the relevant spec files and verify against the new code — do not skim or trust the diff alone."
+
+printf '{"decision": "block", "reason": %s}' "$(printf '%s' "$REASON" | jq -Rs .)"

.claude/settings.json

@@ -4,6 +4,13 @@
       {
         "matcher": "Bash",
         "hooks": [
+          {
+            "type": "command",
+            "if": "Bash(*git commit*)",
+            "command": "\"$CLAUDE_PROJECT_DIR\"/.claude/hooks/pre-commit-spec.sh",
+            "timeout": 30,
+            "statusMessage": "Checking spec drift..."
+          },
           {
             "type": "command",
             "if": "Bash(*git commit*)",