add db connection, refactor code, add db migration files

db/migrations/000002_create_modules.up.sql

@@ -0,0 +1,31 @@
+CREATE TABLE IF NOT EXISTS modules (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    text_id VARCHAR(256) NOT NULL,
+    title VARCHAR(256) NOT NULL,
+    description TEXT NOT NULL,
+    url VARCHAR(256) NOT NULL, 
+    version VARCHAR(64) NOT NULL,
+    availability INTEGER NOT NULL,
+
+    created_at DATETIME NOT NULL DEFAULT current_timestamp
+);
+
+CREATE TABLE IF NOT EXISTS modules_compatibility (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    model_id INTEGER UNIQUE,
+    minimum VARCHAR(64) NOT NULL,
+    verified VARCHAR(64) NOT NULL,
+    maximum VARCHAR(64) NOT NULL,
+
+    FOREIGN KEY (model_id) REFERENCES modules(id) ON DELETE CASCADE
+);
+
+CREATE TABLE IF NOT EXISTS modules_languages (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    model_id INTEGER,
+    language VARCHAR(256) NOT NULL,
+    name VARCHAR(256) NOT NULL, 
+    path VARCHAR(256) NOT NULL, 
+
+    FOREIGN KEY (model_id) REFERENCES modules(id) ON DELETE CASCADE
+);