Added migration file for goal table

Author: ch00z00

backend/db/migrations/000002_create_goals_table.down.sql

@@ -0,0 +1,2 @@
+-- This migration will drop the goals table if it exists
+DROP TABLE IF EXISTS goals;

backend/db/migrations/000002_create_goals_table.up.sql

@@ -0,0 +1,12 @@
+CREATE TABLE goals (
+    id INT AUTO_INCREMENT PRIMARY KEY,
+    user_id VARCHAR(36) NOT NULL,
+    complex_id INT NOT NULL,
+    surface_goal VARCHAR(255) NOT NULL,
+    underlying_goal VARCHAR(255) NOT NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+    INDEX idx_user_id_goal (user_id),
+    INDEX idx_complex_id_goal (complex_id),
+    FOREIGN KEY (complex_id) REFERENCES complexes(id) ON DELETE CASCADE
+);