change db from sqlite3 to postgresql

assets/migrations/sqlite3/20250103140557_response_cache.sql

@@ -0,0 +1,13 @@
+-- +goose Up
+-- +goose StatementBegin
+CREATE TABLE responses (
+    url             VARCHAR(255) NOT NULL UNIQUE PRIMARY KEY,
+    content         TEXT NOT NULL,
+    fetchDate       DATETIME DEFAULT CURRENT_TIMESTAMP
+);
+-- +goose StatementEnd
+
+-- +goose Down
+-- +goose StatementBegin
+DROP TABLE responses;
+-- +goose StatementEnd