feat(workflow): enrich workflow/agent metadata from workflowProgress;

lightweight workflowTree, build debounce, minor fixes

  - Index phase, label, model, state, duration, tokens per workflow agent
  - Index duration, total_tokens, status, name per workflow run
  - workflowTree returns parsed result + agent summaries instead of
    dumping all messages
  - 30s debounce on buildIndex to avoid repeated directory scans
  - Fix broken BASH_EXIT_PAT (SQLite LIKE has no character classes)
  - Fix SKILL.md step numbering, document FTS5 hyphen limitation

scripts/db.mjs

@@ -31,10 +31,13 @@ CREATE TABLE IF NOT EXISTS subagents (
   agent_type TEXT, description TEXT, duration_ms INTEGER, total_tokens INTEGER);
 CREATE TABLE IF NOT EXISTS workflows (
   run_id TEXT PRIMARY KEY, session_id TEXT, task_id TEXT,
-  script TEXT, result_json TEXT, timestamp TEXT, agent_count INTEGER DEFAULT 0);
+  script TEXT, result_json TEXT, timestamp TEXT, agent_count INTEGER DEFAULT 0,
+  duration_ms INTEGER, total_tokens INTEGER, status TEXT, workflow_name TEXT);
 CREATE TABLE IF NOT EXISTS workflow_agents (
   agent_id TEXT PRIMARY KEY, run_id TEXT, session_id TEXT,
-  agent_type TEXT, description TEXT);
+  agent_type TEXT, description TEXT,
+  phase TEXT, label TEXT, model TEXT, state TEXT,
+  duration_ms INTEGER, tokens INTEGER, tool_calls INTEGER);
 CREATE TABLE IF NOT EXISTS index_state (
   jsonl_path TEXT PRIMARY KEY, mtime REAL, lines_processed INTEGER);
 CREATE TABLE IF NOT EXISTS summaries (