feat: Phase 0 walking skeleton — monorepo, API, web, ML stub

Sets up the full Phase 0 foundation:

- pnpm workspaces + turbo build graph; native module build approval
- packages/shared-types: HTTP contracts (Tip, Auth, Integrations, User)
- services/api: Express modular monolith with better-sqlite3/drizzle
  - auth: Google OAuth2 + PKCE via openid-client v6, cookie sessions
  - integrations: Todoist OAuth2 connect/disconnect, token vault
  - recommender: RandomPolicy over Todoist tasks, feedback sink
  - user: profile, consent capture, full account deletion (GDPR)
- apps/web: Next.js 15, three pages (sign-in → connect → tip)
  - tip page: black canvas, hold-to-act gesture, action sheet
  - PWA manifest + theme
- ml/serving: FastAPI stub implementing the POST /score contract
- infra: docker-compose (core/full profiles), Dockerfiles, CI skeleton
- .env.example with all required vars documented

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

packages/shared-types/package.json

@@ -0,0 +1,21 @@
+{
+  "name": "@oo/shared-types",
+  "version": "0.0.0",
+  "private": true,
+  "main": "./dist/index.js",
+  "types": "./dist/index.d.ts",
+  "exports": {
+    ".": {
+      "import": "./dist/index.js",
+      "types": "./dist/index.d.ts"
+    }
+  },
+  "scripts": {
+    "build": "tsc",
+    "type-check": "tsc --noEmit",
+    "clean": "rm -rf dist"
+  },
+  "devDependencies": {
+    "typescript": "^5.7.3"
+  }
+}

packages/shared-types/src/http/auth.ts

@@ -0,0 +1,12 @@
+/** Session user returned by /api/auth/session */
+export interface SessionUser {
+  id: string;
+  email: string;
+  name?: string;
+  image?: string;
+}
+
+/** GET /api/auth/session response */
+export interface SessionResponse {
+  user: SessionUser | null;
+}

packages/shared-types/src/http/integrations.ts

@@ -0,0 +1,18 @@
+export type IntegrationProvider = 'todoist';
+export type IntegrationStatus = 'connected' | 'disconnected' | 'error';
+
+export interface Integration {
+  provider: IntegrationProvider;
+  status: IntegrationStatus;
+  connectedAt?: string; // ISO 8601
+}
+
+/** GET /api/integrations response */
+export interface IntegrationsResponse {
+  integrations: Integration[];
+}
+
+/** DELETE /api/integrations/:provider — revokes token */
+export interface DisconnectResponse {
+  ok: boolean;
+}

packages/shared-types/src/http/tip.ts

@@ -0,0 +1,19 @@
+/** A single recommendation surfaced to the user */
+export interface Tip {
+  id: string;
+  content: string;
+  source: 'todoist' | 'advice';
+  sourceId?: string;
+  createdAt: string; // ISO 8601
+}
+
+/** POST /recommend response */
+export interface RecommendResponse {
+  tip: Tip;
+}
+
+/** POST /tip/:id/feedback request body */
+export interface TipFeedback {
+  action: 'done' | 'dismiss' | 'snooze';
+  snoozedUntil?: string; // ISO 8601, required when action = snooze
+}

packages/shared-types/src/http/user.ts

@@ -0,0 +1,14 @@
+/** GET /api/user/me */
+export interface UserProfile {
+  id: string;
+  email: string;
+  name?: string;
+  image?: string;
+  createdAt: string;
+  consentGiven: boolean;
+}
+
+/** DELETE /api/user/me — account deletion */
+export interface DeleteAccountResponse {
+  ok: boolean;
+}

packages/shared-types/src/index.ts

@@ -0,0 +1,4 @@
+export * from './http/tip.js';
+export * from './http/auth.js';
+export * from './http/integrations.js';
+export * from './http/user.js';

packages/shared-types/tsconfig.json

@@ -0,0 +1,8 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "outDir": "dist",
+    "rootDir": "src"
+  },
+  "include": ["src"]
+}