feat: implement backend core with repricing logic, case management, and multi-service architecture

db/init.sql

@@ -5,10 +5,26 @@ CREATE TABLE IF NOT EXISTS users (
     id SERIAL PRIMARY KEY,
     username VARCHAR(50) UNIQUE NOT NULL,
     password_hash TEXT NOT NULL,
+    role VARCHAR(20) DEFAULT 'admin', -- admin, manager, viewer
+    parent_id INT REFERENCES users(id) ON DELETE CASCADE,
     plan VARCHAR(20) DEFAULT 'free',
     created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
 );
 
+CREATE TABLE IF NOT EXISTS repricer_rules (
+    id SERIAL PRIMARY KEY,
+    user_id INT REFERENCES users(id) ON DELETE CASCADE,
+    product_name VARCHAR(255) NOT NULL,
+    sku VARCHAR(100) NOT NULL,
+    min_price DECIMAL(10, 2) NOT NULL,
+    max_price DECIMAL(10, 2) NOT NULL,
+    strategy VARCHAR(20) DEFAULT 'follow_competitor', -- follow_competitor, match_lowest
+    is_active BOOLEAN DEFAULT TRUE,
+    current_price DECIMAL(10, 2),
+    last_run TIMESTAMP,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
 CREATE TABLE IF NOT EXISTS credentials (
     user_id INT REFERENCES users(id) ON DELETE CASCADE,
     platform VARCHAR(50),