v2.0.0: Multi-user authentication with JWT

Features:
- User registration and login with JWT tokens
- All data is now user-specific (multi-tenancy)
- Profile page with integrations and logout
- Automatic migration of existing data to first user

Backend changes:
- Added users and refresh_tokens tables
- Added user_id to all data tables (projects, entries, nodes, dictionaries, words, progress, configs, telegram_integrations, weekly_goals)
- JWT authentication middleware
- claimOrphanedData() for data migration

Frontend changes:
- AuthContext for state management
- Login/Register forms
- Profile page (replaced Integrations)
- All API calls use authFetch with Bearer token

Migration notes:
- On first deploy, backend automatically adds user_id columns
- First user to login claims all existing data

play-life-backend/migrations/009_add_users_and_multitenancy.sql

@@ -0,0 +1,128 @@
+-- Migration: Add users table and user_id to all tables for multi-tenancy
+-- This script adds user authentication and makes all data user-specific
+-- All statements use IF NOT EXISTS / IF EXISTS for idempotency
+
+-- ============================================
+-- Table: users
+-- ============================================
+CREATE TABLE IF NOT EXISTS users (
+    id SERIAL PRIMARY KEY,
+    email VARCHAR(255) NOT NULL UNIQUE,
+    password_hash VARCHAR(255) NOT NULL,
+    name VARCHAR(255),
+    created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP,
+    is_active BOOLEAN DEFAULT TRUE,
+    last_login_at TIMESTAMP WITH TIME ZONE
+);
+
+CREATE INDEX IF NOT EXISTS idx_users_email ON users(email);
+
+-- ============================================
+-- Table: refresh_tokens
+-- ============================================
+CREATE TABLE IF NOT EXISTS refresh_tokens (
+    id SERIAL PRIMARY KEY,
+    user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    token_hash VARCHAR(255) NOT NULL,
+    expires_at TIMESTAMP WITH TIME ZONE NOT NULL,
+    created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE INDEX IF NOT EXISTS idx_refresh_tokens_user_id ON refresh_tokens(user_id);
+CREATE INDEX IF NOT EXISTS idx_refresh_tokens_token_hash ON refresh_tokens(token_hash);
+
+-- ============================================
+-- Add user_id to projects
+-- ============================================
+ALTER TABLE projects 
+ADD COLUMN IF NOT EXISTS user_id INTEGER REFERENCES users(id) ON DELETE CASCADE;
+
+CREATE INDEX IF NOT EXISTS idx_projects_user_id ON projects(user_id);
+
+-- Drop old unique constraint (name now unique per user, handled in app)
+ALTER TABLE projects DROP CONSTRAINT IF EXISTS unique_project_name;
+
+-- ============================================
+-- Add user_id to entries
+-- ============================================
+ALTER TABLE entries 
+ADD COLUMN IF NOT EXISTS user_id INTEGER REFERENCES users(id) ON DELETE CASCADE;
+
+CREATE INDEX IF NOT EXISTS idx_entries_user_id ON entries(user_id);
+
+-- ============================================
+-- Add user_id to dictionaries
+-- ============================================
+ALTER TABLE dictionaries 
+ADD COLUMN IF NOT EXISTS user_id INTEGER REFERENCES users(id) ON DELETE CASCADE;
+
+CREATE INDEX IF NOT EXISTS idx_dictionaries_user_id ON dictionaries(user_id);
+
+-- ============================================
+-- Add user_id to words
+-- ============================================
+ALTER TABLE words 
+ADD COLUMN IF NOT EXISTS user_id INTEGER REFERENCES users(id) ON DELETE CASCADE;
+
+CREATE INDEX IF NOT EXISTS idx_words_user_id ON words(user_id);
+
+-- ============================================
+-- Add user_id to progress
+-- ============================================
+ALTER TABLE progress 
+ADD COLUMN IF NOT EXISTS user_id INTEGER REFERENCES users(id) ON DELETE CASCADE;
+
+CREATE INDEX IF NOT EXISTS idx_progress_user_id ON progress(user_id);
+
+-- Drop old unique constraint (word_id now unique per user)
+ALTER TABLE progress DROP CONSTRAINT IF EXISTS progress_word_id_key;
+
+-- Create new unique constraint per user
+CREATE UNIQUE INDEX IF NOT EXISTS idx_progress_word_user_unique ON progress(word_id, user_id);
+
+-- ============================================
+-- Add user_id to configs
+-- ============================================
+ALTER TABLE configs 
+ADD COLUMN IF NOT EXISTS user_id INTEGER REFERENCES users(id) ON DELETE CASCADE;
+
+CREATE INDEX IF NOT EXISTS idx_configs_user_id ON configs(user_id);
+
+-- ============================================
+-- Add user_id to telegram_integrations
+-- ============================================
+ALTER TABLE telegram_integrations 
+ADD COLUMN IF NOT EXISTS user_id INTEGER REFERENCES users(id) ON DELETE CASCADE;
+
+CREATE INDEX IF NOT EXISTS idx_telegram_integrations_user_id ON telegram_integrations(user_id);
+
+-- ============================================
+-- Add user_id to weekly_goals
+-- ============================================
+ALTER TABLE weekly_goals 
+ADD COLUMN IF NOT EXISTS user_id INTEGER REFERENCES users(id) ON DELETE CASCADE;
+
+CREATE INDEX IF NOT EXISTS idx_weekly_goals_user_id ON weekly_goals(user_id);
+
+-- ============================================
+-- Add user_id to nodes (score data)
+-- ============================================
+ALTER TABLE nodes 
+ADD COLUMN IF NOT EXISTS user_id INTEGER REFERENCES users(id) ON DELETE CASCADE;
+
+CREATE INDEX IF NOT EXISTS idx_nodes_user_id ON nodes(user_id);
+
+-- ============================================
+-- Comments for documentation
+-- ============================================
+COMMENT ON TABLE users IS 'Users table for authentication and multi-tenancy';
+COMMENT ON COLUMN users.email IS 'User email address (unique, used for login)';
+COMMENT ON COLUMN users.password_hash IS 'Bcrypt hashed password';
+COMMENT ON COLUMN users.name IS 'User display name';
+COMMENT ON COLUMN users.is_active IS 'Whether the user account is active';
+COMMENT ON TABLE refresh_tokens IS 'JWT refresh tokens for persistent login';
+
+-- Note: The first user who logs in will automatically become the owner of all
+-- existing data (projects, entries, dictionaries, words, etc.) that have NULL user_id.
+-- This is handled in the application code (claimOrphanedData function).