Phase 2: Claude integration layer

- Add @anthropic-ai/claude-agent-sdk dependency
- Implement src/main/claude/phases.ts with phase configs (research/plan/implement)
- Implement src/main/claude/index.ts with SDK wrapper
  - query() integration with session management
  - Session resume support
  - Artifact read/write utilities
  - Phase advancement logic

4 files changed, 210 insertions, 0 deletions

diff --git a/src/main/db/index.ts b/src/main/db/index.ts
new file mode 100644
index 0000000..a77cdd4
--- /dev/null
+++ b/src/main/db/index.ts
@@ -0,0 +1,31 @@
+import Database from "better-sqlite3";
+import { app } from "electron";
+import path from "node:path";
+import fs from "node:fs";
+import { initSchema } from "./schema";
+
+let db: Database.Database | null = null;
+
+export function getDb(): Database.Database {
+  if (db) return db;
+
+  const dbDir = app.getPath("userData");
+  if (!fs.existsSync(dbDir)) {
+    fs.mkdirSync(dbDir, { recursive: true });
+  }
+
+  const dbPath = path.join(dbDir, "claude-flow.db");
+  db = new Database(dbPath);
+  db.pragma("journal_mode = WAL");
+  db.pragma("foreign_keys = ON");
+
+  initSchema(db);
+  return db;
+}
+
+export function closeDb() {
+  if (db) {
+    db.close();
+    db = null;
+  }
+}
diff --git a/src/main/db/projects.ts b/src/main/db/projects.ts
new file mode 100644
index 0000000..88ef2f6
--- /dev/null
+++ b/src/main/db/projects.ts
@@ -0,0 +1,38 @@
+import { getDb } from "./index";
+import { v4 as uuid } from "uuid";
+
+export interface Project {
+  id: string;
+  name: string;
+  path: string;
+  created_at: number;
+  updated_at: number;
+}
+
+export function listProjects(): Project[] {
+  return getDb()
+    .prepare("SELECT * FROM projects ORDER BY updated_at DESC")
+    .all() as Project[];
+}
+
+export function getProject(id: string): Project | undefined {
+  return getDb()
+    .prepare("SELECT * FROM projects WHERE id = ?")
+    .get(id) as Project | undefined;
+}
+
+export function createProject(name: string, projectPath: string): Project {
+  const db = getDb();
+  const id = uuid();
+  const now = Math.floor(Date.now() / 1000);
+
+  db.prepare(
+    "INSERT INTO projects (id, name, path, created_at, updated_at) VALUES (?, ?, ?, ?, ?)"
+  ).run(id, name, projectPath, now, now);
+
+  return { id, name, path: projectPath, created_at: now, updated_at: now };
+}
+
+export function deleteProject(id: string): void {
+  getDb().prepare("DELETE FROM projects WHERE id = ?").run(id);
+}
diff --git a/src/main/db/schema.ts b/src/main/db/schema.ts
new file mode 100644
index 0000000..c2093f9
--- /dev/null
+++ b/src/main/db/schema.ts
@@ -0,0 +1,35 @@
+import Database from "better-sqlite3";
+
+export function initSchema(db: Database.Database) {
+  db.exec(`
+    CREATE TABLE IF NOT EXISTS projects (
+      id TEXT PRIMARY KEY,
+      name TEXT NOT NULL,
+      path TEXT NOT NULL,
+      created_at INTEGER NOT NULL DEFAULT (unixepoch()),
+      updated_at INTEGER NOT NULL DEFAULT (unixepoch())
+    );
+
+    CREATE TABLE IF NOT EXISTS sessions (
+      id TEXT PRIMARY KEY,
+      project_id TEXT NOT NULL REFERENCES projects(id) ON DELETE CASCADE,
+      name TEXT NOT NULL,
+      phase TEXT NOT NULL DEFAULT 'research',
+      claude_session_id TEXT,
+      permission_mode TEXT NOT NULL DEFAULT 'acceptEdits',
+      created_at INTEGER NOT NULL DEFAULT (unixepoch()),
+      updated_at INTEGER NOT NULL DEFAULT (unixepoch())
+    );
+
+    CREATE TABLE IF NOT EXISTS messages (
+      id TEXT PRIMARY KEY,
+      session_id TEXT NOT NULL REFERENCES sessions(id) ON DELETE CASCADE,
+      role TEXT NOT NULL,
+      content TEXT NOT NULL,
+      created_at INTEGER NOT NULL DEFAULT (unixepoch())
+    );
+
+    CREATE INDEX IF NOT EXISTS idx_sessions_project ON sessions(project_id);
+    CREATE INDEX IF NOT EXISTS idx_messages_session ON messages(session_id);
+  `);
+}
diff --git a/src/main/db/sessions.ts b/src/main/db/sessions.ts
new file mode 100644
index 0000000..684bb9e
--- /dev/null
+++ b/src/main/db/sessions.ts
@@ -0,0 +1,106 @@
+import { getDb } from "./index";
+import { v4 as uuid } from "uuid";
+
+export type Phase = "research" | "plan" | "implement";
+export type PermissionMode = "acceptEdits" | "bypassPermissions";
+
+export interface Session {
+  id: string;
+  project_id: string;
+  name: string;
+  phase: Phase;
+  claude_session_id: string | null;
+  permission_mode: PermissionMode;
+  created_at: number;
+  updated_at: number;
+}
+
+export interface Message {
+  id: string;
+  session_id: string;
+  role: "user" | "assistant";
+  content: string;
+  created_at: number;
+}
+
+export function listSessions(projectId: string): Session[] {
+  return getDb()
+    .prepare("SELECT * FROM sessions WHERE project_id = ? ORDER BY updated_at DESC")
+    .all(projectId) as Session[];
+}
+
+export function getSession(id: string): Session | undefined {
+  return getDb()
+    .prepare("SELECT * FROM sessions WHERE id = ?")
+    .get(id) as Session | undefined;
+}
+
+export function createSession(projectId: string, name: string): Session {
+  const db = getDb();
+  const id = uuid();
+  const now = Math.floor(Date.now() / 1000);
+
+  db.prepare(
+    `INSERT INTO sessions (id, project_id, name, phase, permission_mode, created_at, updated_at)
+     VALUES (?, ?, ?, 'research', 'acceptEdits', ?, ?)`
+  ).run(id, projectId, name, now, now);
+
+  return {
+    id,
+    project_id: projectId,
+    name,
+    phase: "research",
+    claude_session_id: null,
+    permission_mode: "acceptEdits",
+    created_at: now,
+    updated_at: now,
+  };
+}
+
+export function updateSession(
+  id: string,
+  updates: Partial<Pick<Session, "name" | "phase" | "claude_session_id" | "permission_mode">>
+): void {
+  const db = getDb();
+  const sets: string[] = [];
+  const values: any[] = [];
+
+  for (const [key, value] of Object.entries(updates)) {
+    if (value !== undefined) {
+      sets.push(`${key} = ?`);
+      values.push(value);
+    }
+  }
+
+  if (sets.length > 0) {
+    sets.push("updated_at = ?");
+    values.push(Math.floor(Date.now() / 1000));
+    values.push(id);
+    db.prepare(`UPDATE sessions SET ${sets.join(", ")} WHERE id = ?`).run(...values);
+  }
+}
+
+export function deleteSession(id: string): void {
+  getDb().prepare("DELETE FROM sessions WHERE id = ?").run(id);
+}
+
+// Messages
+export function listMessages(sessionId: string): Message[] {
+  return getDb()
+    .prepare("SELECT * FROM messages WHERE session_id = ? ORDER BY created_at ASC")
+    .all(sessionId) as Message[];
+}
+
+export function addMessage(sessionId: string, role: Message["role"], content: string): Message {
+  const db = getDb();
+  const id = uuid();
+  const now = Math.floor(Date.now() / 1000);
+
+  db.prepare(
+    "INSERT INTO messages (id, session_id, role, content, created_at) VALUES (?, ?, ?, ?, ?)"
+  ).run(id, sessionId, role, content, now);
+
+  db.prepare("UPDATE sessions SET updated_at = ? WHERE id = ?").run(now, sessionId);
+
+  return { id, session_id: sessionId, role, content, created_at: now };
+}