feat: US-002 — SQLite + Drizzle ORM schema and migrations

- Install better-sqlite3 + drizzle-orm as runtime deps; drizzle-kit + @types/better-sqlite3 as devDeps
- Define 5 tables in src/main/db/schema.ts: clients, projects, tasks, checkpoints, notes
- All IDs are TEXT (UUID); types inferred via InferSelectModel/InferInsertModel
- initDb() in src/main/db/index.ts opens adiuva.db at app.getPath('userData'), runs CREATE TABLE IF NOT EXISTS (non-destructive push), enables WAL mode
- Call initDb() in main process app ready handler
- Externalize better-sqlite3 in vite.main.config.mts; add AutoUnpackNativesPlugin to forge.config.ts
- Add drizzle.config.ts for drizzle-kit CLI support

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

src/main/db/index.ts

@@ -0,0 +1,83 @@
+import Database from 'better-sqlite3';
+import { drizzle } from 'drizzle-orm/better-sqlite3';
+import { app } from 'electron';
+import path from 'node:path';
+import * as schema from './schema';
+
+// SQL to create all tables if they don't exist (non-destructive push strategy)
+const MIGRATION_SQL = `
+  CREATE TABLE IF NOT EXISTS clients (
+    id TEXT PRIMARY KEY,
+    parent_id TEXT,
+    name TEXT NOT NULL,
+    industry TEXT,
+    created_at INTEGER NOT NULL
+  );
+
+  CREATE TABLE IF NOT EXISTS projects (
+    id TEXT PRIMARY KEY,
+    client_id TEXT,
+    name TEXT NOT NULL,
+    status TEXT NOT NULL DEFAULT 'active',
+    ai_summary TEXT,
+    created_at INTEGER NOT NULL
+  );
+
+  CREATE TABLE IF NOT EXISTS tasks (
+    id TEXT PRIMARY KEY,
+    project_id TEXT,
+    title TEXT NOT NULL,
+    description TEXT,
+    status TEXT NOT NULL DEFAULT 'todo',
+    priority TEXT NOT NULL DEFAULT 'medium',
+    assignee TEXT,
+    due_date INTEGER,
+    created_at INTEGER NOT NULL
+  );
+
+  CREATE TABLE IF NOT EXISTS checkpoints (
+    id TEXT PRIMARY KEY,
+    project_id TEXT NOT NULL,
+    title TEXT NOT NULL,
+    date INTEGER NOT NULL,
+    is_ai_suggested INTEGER NOT NULL DEFAULT 0,
+    is_approved INTEGER NOT NULL DEFAULT 0,
+    created_at INTEGER NOT NULL
+  );
+
+  CREATE TABLE IF NOT EXISTS notes (
+    id TEXT PRIMARY KEY,
+    project_id TEXT,
+    title TEXT NOT NULL,
+    content TEXT NOT NULL DEFAULT '',
+    created_at INTEGER NOT NULL,
+    updated_at INTEGER NOT NULL
+  );
+`;
+
+type DbInstance = ReturnType<typeof drizzle<typeof schema>>;
+
+let dbInstance: DbInstance | null = null;
+
+export function initDb(): DbInstance {
+  const userDataPath = app.getPath('userData');
+  const dbPath = path.join(userDataPath, 'adiuva.db');
+
+  const sqlite = new Database(dbPath);
+
+  // Enable WAL mode for better concurrent read performance
+  sqlite.pragma('journal_mode = WAL');
+
+  // Run non-destructive migrations on every start
+  sqlite.exec(MIGRATION_SQL);
+
+  dbInstance = drizzle(sqlite, { schema });
+  return dbInstance;
+}
+
+export function getDb(): DbInstance {
+  if (!dbInstance) {
+    throw new Error('Database not initialized. Call initDb() first.');
+  }
+  return dbInstance;
+}

src/main/db/schema.ts

@@ -0,0 +1,66 @@
+import { sqliteTable, text, integer } from 'drizzle-orm/sqlite-core';
+import type { InferSelectModel, InferInsertModel } from 'drizzle-orm';
+
+export const clients = sqliteTable('clients', {
+  id: text('id').primaryKey(),
+  parentId: text('parent_id'),
+  name: text('name').notNull(),
+  industry: text('industry'),
+  createdAt: integer('created_at', { mode: 'number' }).notNull(),
+});
+
+export const projects = sqliteTable('projects', {
+  id: text('id').primaryKey(),
+  clientId: text('client_id'),
+  name: text('name').notNull(),
+  status: text('status', { enum: ['active', 'archived'] }).notNull().default('active'),
+  aiSummary: text('ai_summary'),
+  createdAt: integer('created_at', { mode: 'number' }).notNull(),
+});
+
+export const tasks = sqliteTable('tasks', {
+  id: text('id').primaryKey(),
+  projectId: text('project_id'),
+  title: text('title').notNull(),
+  description: text('description'),
+  status: text('status').notNull().default('todo'),
+  priority: text('priority').notNull().default('medium'),
+  assignee: text('assignee'),
+  dueDate: integer('due_date', { mode: 'number' }),
+  createdAt: integer('created_at', { mode: 'number' }).notNull(),
+});
+
+export const checkpoints = sqliteTable('checkpoints', {
+  id: text('id').primaryKey(),
+  projectId: text('project_id').notNull(),
+  title: text('title').notNull(),
+  date: integer('date', { mode: 'number' }).notNull(),
+  isAiSuggested: integer('is_ai_suggested', { mode: 'number' }).notNull().default(0),
+  isApproved: integer('is_approved', { mode: 'number' }).notNull().default(0),
+  createdAt: integer('created_at', { mode: 'number' }).notNull(),
+});
+
+export const notes = sqliteTable('notes', {
+  id: text('id').primaryKey(),
+  projectId: text('project_id'),
+  title: text('title').notNull(),
+  content: text('content').notNull().default(''),
+  createdAt: integer('created_at', { mode: 'number' }).notNull(),
+  updatedAt: integer('updated_at', { mode: 'number' }).notNull(),
+});
+
+// Inferred TypeScript types — no manual duplication
+export type Client = InferSelectModel<typeof clients>;
+export type NewClient = InferInsertModel<typeof clients>;
+
+export type Project = InferSelectModel<typeof projects>;
+export type NewProject = InferInsertModel<typeof projects>;
+
+export type Task = InferSelectModel<typeof tasks>;
+export type NewTask = InferInsertModel<typeof tasks>;
+
+export type Checkpoint = InferSelectModel<typeof checkpoints>;
+export type NewCheckpoint = InferInsertModel<typeof checkpoints>;
+
+export type Note = InferSelectModel<typeof notes>;
+export type NewNote = InferInsertModel<typeof notes>;

src/main/index.ts

@@ -1,6 +1,7 @@
 import { app, BrowserWindow } from 'electron';
 import path from 'node:path';
 import started from 'electron-squirrel-startup';
+import { initDb } from './db';
 
 // Handle creating/removing shortcuts on Windows when installing/uninstalling.
 if (started) {
@@ -40,7 +41,10 @@ const createWindow = () => {
 // This method will be called when Electron has finished
 // initialization and is ready to create browser windows.
 // Some APIs can only be used after this event occurs.
-app.on('ready', createWindow);
+app.on('ready', () => {
+  initDb();
+  createWindow();
+});
 
 // Quit when all windows are closed, except on macOS. There, it's common
 // for applications and their menu bar to stay active until the user quits