Add new Instance methods, add tests for it as well

tests/entities/Instance.test.ts

@@ -0,0 +1,40 @@
+import { afterAll, beforeAll, describe, expect, it } from "bun:test";
+import { AppDataSource } from "~database/datasource";
+import { Instance } from "~database/entities/Instance";
+
+let instance: Instance;
+
+beforeAll(async () => {
+	if (!AppDataSource.isInitialized) await AppDataSource.initialize();
+});
+
+describe("Instance", () => {
+	it("should add an instance to the database if it doesn't already exist", async () => {
+		const url = "https://mastodon.social";
+		instance = await Instance.addIfNotExists(url);
+		expect(instance.base_url).toBe("mastodon.social");
+	});
+
+	it("should convert the instance to an API instance", async () => {
+		const apiInstance = await instance.toAPI();
+		expect(apiInstance.uri).toBe("mastodon.social");
+		expect(apiInstance.approval_required).toBe(false);
+		expect(apiInstance.email).toBe("staff@mastodon.social");
+		expect(apiInstance.thumbnail).toBeDefined();
+		expect(apiInstance.title).toBeDefined();
+		expect(apiInstance.configuration).toBeDefined();
+		expect(apiInstance.contact_account).toBeDefined();
+		expect(apiInstance.description).toBeDefined();
+		expect(apiInstance.invites_enabled).toBeDefined();
+		expect(apiInstance.languages).toBeDefined();
+		expect(apiInstance.registrations).toBeDefined();
+		expect(apiInstance.rules).toBeDefined();
+		expect(apiInstance.stats).toBeDefined();
+		expect(apiInstance.urls).toBeDefined();
+		expect(apiInstance.max_toot_chars).toBeDefined();
+	});
+});
+
+afterAll(async () => {
+	await instance.remove();
+});