changesets: add changesets for frontend-plugin-api tsdocs

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

.changeset/whole-glasses-visit.md

@@ -0,0 +1,5 @@
+---
+'@backstage/frontend-plugin-api': patch
+---
+
+Added inline documentation for `createExtension`, `createExtensionBlueprint`, `createFrontendPlugin`, and `createFrontendModule`.

packages/frontend-plugin-api/report.api.md

@@ -393,7 +393,7 @@ export { createApiFactory };
 
 export { createApiRef };
 
-// @public (undocumented)
+// @public
 export function createExtension<
   UOutput extends ExtensionDataRef,
   TInputs extends {
@@ -688,7 +688,7 @@ export interface CreateFrontendFeatureLoaderOptions {
       >;
 }
 
-// @public (undocumented)
+// @public
 export function createFrontendModule<
   TId extends string,
   TExtensions extends readonly ExtensionDefinition[] = [],
@@ -707,7 +707,7 @@ export interface CreateFrontendModuleOptions<
   pluginId: TPluginId;
 }
 
-// @public (undocumented)
+// @public
 export function createFrontendPlugin<
   TId extends string,
   TRoutes extends {