fix(core): re-arm plugin command watchers when sources are unchanged

The early return skipped watch(), so a watcher parked on an ancestor stayed
there after an empty plugins directory was created, and a plugin added later
was never discovered.

Co-authored-by: Saoud Rizwan <saoudrizwan@users.noreply.github.com>

sdk/packages/core/src/services/plugin-commands.test.ts

@@ -181,6 +181,23 @@ describe("runtime plugin catalogs", () => {
 			{ timeout: 3000 },
 		);
 	});
+	it("discovers plugins added after an empty plugins directory appears", async () => {
+		const workspacePath = await workspace();
+		await mkdir(join(workspacePath, ".cline"));
+		const load = vi.fn(async () => loaded());
+		const manager = new PluginCommandManager({ load });
+		managers.push(manager);
+		await manager.list({ workspacePath });
+		const directory = join(workspacePath, ".cline", "plugins");
+		await mkdir(directory);
+		await new Promise((resolve) => setTimeout(resolve, 500));
+		const calls = load.mock.calls.length;
+		await writeFile(join(directory, "echo.js"), "export default {};");
+		await vi.waitFor(
+			() => expect(load.mock.calls.length).toBeGreaterThan(calls),
+			{ timeout: 3000 },
+		);
+	});
 	it.each([
 		"add",
 		"edit",

sdk/packages/core/src/services/plugin-commands.ts

@@ -233,8 +233,11 @@ export class PluginCommandManager implements PluginCommandsApi {
 						sourceKey !== undefined &&
 						sourceKey === entry.sourceKey &&
 						entry.failedPaths?.length === 0
-					)
+					) {
+						// A watched root may have just been created; move the watchers into it.
+						this.watch(entry);
 						return;
+					}
 					entry.sourceKey = sourceKey;
 					await Promise.all(
 						entry.loaded.map((loaded) => loaded.shutdown?.().catch(() => {})),