refactor(instance-store): consolidate dispose helpers (#25424)

packages/opencode/src/cli/bootstrap.ts

@@ -9,7 +9,7 @@ export async function bootstrap<T>(directory: string, cb: () => Promise<T>) {
         const result = await cb()
         return result
       } finally {
-        await InstanceStore.runtime.runPromise((s) => s.dispose(Instance.current))
+        await InstanceStore.disposeInstance(Instance.current)
       }
     },
   })

packages/opencode/src/cli/cmd/tui/worker.ts

@@ -88,7 +88,7 @@ export const rpc = {
   async shutdown() {
     Log.Default.info("worker shutting down")
 
-    await InstanceStore.runtime.runPromise((s) => s.disposeAll())
+    await InstanceStore.disposeAllInstances()
     if (server) await server.stop(true)
   },
 }