refactor: split types.ts into domain modules (phase 4, step 1)

Split 1,443-line types.ts into 14 focused domain files under src/types/:
common.ts, session.ts, task.ts, app-state.ts, respawn.ts, ralph.ts,
api.ts, lifecycle.ts, run-summary.ts, tools.ts, teams.ts, push.ts,
plan.ts, and index.ts barrel.

Moved PlanItem interface from plan-orchestrator.ts into types/plan.ts
to break circular dependency. Original types.ts replaced with barrel
re-export — zero changes to 36 import sites.

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

src/types/app-state.ts

@@ -0,0 +1,154 @@
+/**
+ * @fileoverview Application state type definitions
+ */
+
+import type { SessionState } from './session.js';
+import type { TaskState } from './task.js';
+import type { RalphLoopState } from './ralph.js';
+import type { RespawnConfig } from './respawn.js';
+
+// ========== Global Stats Types ==========
+
+/**
+ * Global statistics across all sessions (including deleted ones).
+ * Persisted to track cumulative usage over time.
+ */
+export interface GlobalStats {
+  /** Total input tokens used across all sessions */
+  totalInputTokens: number;
+  /** Total output tokens used across all sessions */
+  totalOutputTokens: number;
+  /** Total cost in USD across all sessions */
+  totalCost: number;
+  /** Total number of sessions created (lifetime) */
+  totalSessionsCreated: number;
+  /** Timestamp when stats were first recorded */
+  firstRecordedAt: number;
+  /** Timestamp of last update */
+  lastUpdatedAt: number;
+}
+
+// ========== Token Usage History Types ==========
+
+/**
+ * Daily token usage entry for historical tracking.
+ */
+export interface TokenUsageEntry {
+  /** Date in YYYY-MM-DD format */
+  date: string;
+  /** Input tokens used on this day */
+  inputTokens: number;
+  /** Output tokens used on this day */
+  outputTokens: number;
+  /** Estimated cost in USD */
+  estimatedCost: number;
+  /** Number of sessions that contributed to this day's usage */
+  sessions: number;
+}
+
+/**
+ * Token usage statistics with daily tracking.
+ */
+export interface TokenStats {
+  /** Daily usage entries (most recent first) */
+  daily: TokenUsageEntry[];
+  /** Timestamp of last update */
+  lastUpdated: number;
+}
+
+/**
+ * Application configuration
+ */
+export interface AppConfig {
+  /** Interval for polling session status (ms) */
+  pollIntervalMs: number;
+  /** Default timeout for tasks (ms) */
+  defaultTimeoutMs: number;
+  /** Maximum concurrent sessions allowed */
+  maxConcurrentSessions: number;
+  /** Path to state file */
+  stateFilePath: string;
+  /** Respawn controller configuration */
+  respawn: RespawnConfig;
+  /** Last used case name (for default selection) */
+  lastUsedCase: string | null;
+  /** Whether Ralph/Todo tracker is globally enabled for all new sessions */
+  ralphEnabled: boolean;
+}
+
+/**
+ * Complete application state
+ */
+export interface AppState {
+  /** Map of session ID to session state */
+  sessions: Record<string, SessionState>;
+  /** Map of task ID to task state */
+  tasks: Record<string, TaskState>;
+  /** Ralph Loop controller state */
+  ralphLoop: RalphLoopState;
+  /** Application configuration */
+  config: AppConfig;
+  /** Global statistics (cumulative across all sessions) */
+  globalStats?: GlobalStats;
+  /** Daily token usage statistics */
+  tokenStats?: TokenStats;
+}
+
+// ========== Default Configuration ==========
+
+/**
+ * Default application configuration values
+ */
+export const DEFAULT_CONFIG: AppConfig = {
+  pollIntervalMs: 1000,
+  defaultTimeoutMs: 300000, // 5 minutes
+  maxConcurrentSessions: 5,
+  stateFilePath: '',
+  respawn: {
+    idleTimeoutMs: 5000, // 5 seconds of no activity after prompt
+    updatePrompt: 'update all the docs and CLAUDE.md',
+    interStepDelayMs: 1000, // 1 second between steps
+    enabled: false, // disabled by default
+    sendClear: true, // send /clear after update prompt
+    sendInit: true, // send /init after /clear
+  },
+  lastUsedCase: null,
+  ralphEnabled: false,
+};
+
+/**
+ * Creates initial application state
+ * @returns Fresh application state with defaults
+ */
+export function createInitialState(): AppState {
+  return {
+    sessions: {},
+    tasks: {},
+    ralphLoop: {
+      status: 'stopped',
+      startedAt: null,
+      minDurationMs: null,
+      tasksCompleted: 0,
+      tasksGenerated: 0,
+      lastCheckAt: null,
+    },
+    config: { ...DEFAULT_CONFIG },
+    globalStats: createInitialGlobalStats(),
+  };
+}
+
+/**
+ * Creates initial global stats object
+ * @returns Fresh global stats with zero values
+ */
+export function createInitialGlobalStats(): GlobalStats {
+  const now = Date.now();
+  return {
+    totalInputTokens: 0,
+    totalOutputTokens: 0,
+    totalCost: 0,
+    totalSessionsCreated: 0,
+    firstRecordedAt: now,
+    lastUpdatedAt: now,
+  };
+}