Declare project and app metadata types (#1470)

* Declare project and app metadata types

* Split metadata.ts into apps.ts and projects.ts

src/management/apps.ts

@@ -0,0 +1,34 @@
+export interface AppMetadata {
+  name: string /* The fully qualified resource name of the Firebase App */;
+  projectId: string;
+  appId: string;
+  platform: AppPlatform;
+  displayName?: string;
+}
+
+export interface IosAppMetadata extends AppMetadata {
+  bundleId: string;
+  appStoreId?: string;
+  platform: AppPlatform.IOS;
+}
+
+export interface AndroidAppMetadata extends AppMetadata {
+  packageName: string;
+  platform: AppPlatform.ANDROID;
+}
+
+export interface WebAppMetadata extends AppMetadata {
+  displayName: string;
+  appUrls?: string[];
+  platform: AppPlatform.WEB;
+}
+
+export enum AppPlatform {
+  PLATFORM_UNSPECIFIED = "PLATFORM_UNSPECIFIED",
+  IOS = "IOS",
+  ANDROID = "ANDROID",
+  WEB = "WEB",
+  ANY = "ANY",
+}
+
+// TODO(caot): Add API methods related to app management into this file

src/management/projects.ts

@@ -0,0 +1,16 @@
+export interface FirebaseProjectMetadata {
+  name: string /* The fully qualified resource name of the Firebase project */;
+  projectId: string;
+  projectNumber: string;
+  displayName: string;
+  resources: DefaultProjectResources;
+}
+
+export interface DefaultProjectResources {
+  hostingSite: string;
+  realtimeDatabaseInstance: string;
+  storageBucket: string;
+  locationId: string;
+}
+
+// TODO(caot): Add API methods related to project management into this file