chore: common services package (#6255)

* fix: initial services package setup

* fix: services packages updates

* fix: services changes

* fix: merge conflicts

* chore: file structuring

* fix: import fixes

packages/services/src/instance/index.ts

@@ -0,0 +1 @@
+export * from "./instance.service";

packages/services/src/instance/instance.service.ts

@@ -0,0 +1,44 @@
+import { API_BASE_URL } from "@plane/constants";
+import type { IInstanceInfo, TPage } from "@plane/types";
+import { APIService } from "@/api.service";
+
+/**
+ * Service class for managing instance-related operations
+ * Handles retrieval of instance information and changelog
+ * @extends {APIService}
+ */
+export default class InstanceService extends APIService {
+  /**
+   * Creates an instance of InstanceService
+   * Initializes the service with the base API URL
+   */
+  constructor() {
+    super(API_BASE_URL);
+  }
+
+  /**
+   * Retrieves information about the current instance
+   * @returns {Promise<IInstanceInfo>} Promise resolving to instance information
+   * @throws {Error} If the API request fails
+   */
+  async info(): Promise<IInstanceInfo> {
+    return this.get("/api/instances/")
+      .then((response) => response.data)
+      .catch((error) => {
+        throw error;
+      });
+  }
+
+  /**
+   * Fetches the changelog for the current instance
+   * @returns {Promise<TPage>} Promise resolving to the changelog page data
+   * @throws {Error} If the API request fails
+   */
+  async changelog(): Promise<TPage> {
+    return this.get("/api/instances/changelog/")
+      .then((response) => response.data)
+      .catch((error) => {
+        throw error;
+      });
+  }
+}