feat(app): embed indexer in Electron with file-watching service and UI refinements

Extract schema DDL into scripts/schema.sql shared between CLI and app.
  Add an in-process chokidar-based indexer-service that watches ~/.claude/projects
  for JSONL changes, debounces, and triggers background rebuilds via a worker
  thread. Rename Usage view to Activity, flesh out MemoryDetail and SubagentDetail
  views, and refine App.vue layout/routing. The main process now starts/stops the
  indexer lifecycle and notifies renderer windows on index updates.

scripts/schema.sql

@@ -0,0 +1,57 @@
+CREATE TABLE IF NOT EXISTS sessions (
+  id TEXT PRIMARY KEY, title TEXT, project TEXT, project_path TEXT,
+  started_at TEXT, ended_at TEXT, git_branch TEXT, version TEXT,
+  message_count INTEGER DEFAULT 0, jsonl_path TEXT);
+CREATE TABLE IF NOT EXISTS messages (
+  uuid TEXT PRIMARY KEY, session_id TEXT, type TEXT, parent_uuid TEXT,
+  timestamp TEXT, role TEXT, text TEXT, content_type TEXT,
+  is_meta INTEGER DEFAULT 0, model TEXT,
+  is_sidechain INTEGER DEFAULT 0, agent_id TEXT,
+  input_tokens INTEGER, output_tokens INTEGER,
+  cwd TEXT, skill TEXT, turn_duration_ms INTEGER);
+CREATE TABLE IF NOT EXISTS tool_calls (
+  id TEXT PRIMARY KEY, message_uuid TEXT, session_id TEXT,
+  name TEXT, input_json TEXT, file_path TEXT);
+CREATE TABLE IF NOT EXISTS tool_results (
+  tool_use_id TEXT PRIMARY KEY, message_uuid TEXT, session_id TEXT,
+  content TEXT, file_path TEXT, is_error INTEGER DEFAULT 0);
+CREATE TABLE IF NOT EXISTS subagents (
+  agent_id TEXT PRIMARY KEY, session_id TEXT, parent_tool_use_id TEXT,
+  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,
+  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,
+  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 (
+  id TEXT PRIMARY KEY, session_id TEXT, timestamp TEXT,
+  source TEXT, content TEXT);
+CREATE VIRTUAL TABLE IF NOT EXISTS messages_fts USING fts5(
+  uuid UNINDEXED, session_id UNINDEXED, text, content=messages, content_rowid=rowid);
+CREATE INDEX IF NOT EXISTS idx_messages_session ON messages(session_id);
+CREATE INDEX IF NOT EXISTS idx_messages_agent ON messages(agent_id);
+CREATE INDEX IF NOT EXISTS idx_messages_ts ON messages(session_id, timestamp);
+CREATE INDEX IF NOT EXISTS idx_tc_session_name ON tool_calls(session_id, name);
+CREATE INDEX IF NOT EXISTS idx_tc_file ON tool_calls(file_path);
+CREATE INDEX IF NOT EXISTS idx_sa_session ON subagents(session_id);
+CREATE INDEX IF NOT EXISTS idx_wf_session ON workflows(session_id);
+CREATE INDEX IF NOT EXISTS idx_wa_run ON workflow_agents(run_id);
+CREATE INDEX IF NOT EXISTS idx_summaries_session ON summaries(session_id);
+CREATE TABLE IF NOT EXISTS memories (
+  id TEXT PRIMARY KEY, session_id TEXT, project TEXT,
+  message_start TEXT, message_end TEXT,
+  path TEXT, anchors TEXT, summary TEXT, created_at TEXT,
+  deleted_at TEXT, deleted_reason TEXT);
+CREATE VIRTUAL TABLE IF NOT EXISTS memories_fts USING fts5(
+  id UNINDEXED, path, summary,
+  content=memories, content_rowid=rowid,
+  tokenize='unicode61 remove_diacritics 1');
+CREATE INDEX IF NOT EXISTS idx_memories_project ON memories(project);
+CREATE INDEX IF NOT EXISTS idx_memories_session ON memories(session_id);
+CREATE INDEX IF NOT EXISTS idx_memories_created ON memories(created_at);