Control surface, not agent brain

provider credentials, or machine state for the environment's. The desktop app bundles a server,
but its renderer follows the same boundary.
 
## Ownership boundaries
 
Provider processes, terminals, Git, and project files belong to the server. Shared connection and
domain state belongs in `packages/client-runtime`; clients supply platform services and UI.
Keeping that logic shared prevents reconnect and multi-environment behavior from diverging between
web and mobile. See [connection runtime](./connection-runtime.md) and
[remote environments](./remote.md).
 
The [RPC contract](../../packages/contracts/src/rpc.ts) is the boundary between independently
versioned clients and servers. Subscriptions send the state a client needs, so a client viewing one
thread does not pay for every thread's history. Authentication of a socket does not authorize every
method on it. See [environment auth](./environment-auth.md).
 
### Pull request linking compatibility
 
Web, desktop, mobile, and environments upgrade independently. Negotiate linking through the
environment descriptor, never through a client version or an assumed coordinated release:
 
| Environment capability                | Client behavior                                                                                                   |
| ------------------------------------- | ----------------------------------------------------------------------------------------------------------------- |
| `threadPullRequests: true`            | Use persisted `pullRequests[]`, multi-link commands, stack UI, and reverse thread lookup.                         |

export interface ProviderAdapterShape<TError> {
  /**
   * Provider kind implemented by this adapter.
   */
  readonly provider: ProviderDriverKind;
  readonly capabilities: ProviderAdapterCapabilities;
 
  /**
   * Start a provider-backed session.
   */
  readonly startSession: (
    input: ProviderSessionStartInput,
  ) => Effect.Effect<ProviderSession, TError>;
 
  /**
   * Send a turn to an active provider session.
   */
  readonly sendTurn: (
    input: ProviderSendTurnInput,
  ) => Effect.Effect<ProviderTurnStartResult, TError>;
 
  /** Omitted when this adapter does not support manual context compaction. */
  readonly compaction?: ProviderCompaction<TError>;
 
  /**
   * Interrupt an active turn.
   */
  readonly interruptTurn: (threadId: ThreadId, turnId?: TurnId) => Effect.Effect<void, TError>;

  /**
   * Stop all sessions owned by this adapter.
   */
  readonly stopAll: () => Effect.Effect<void, TError>;
 
  /**
   * Canonical runtime event stream emitted by this adapter.
   */
  readonly streamEvents: Stream.Stream<ProviderRuntimeEvent>;

  Layer.provideMerge(VcsDriverRegistryLayerLive),
);
 
const VcsLayerLive = Layer.empty.pipe(
  Layer.provideMerge(VcsProjectConfig.layer),
  Layer.provideMerge(VcsDriverRegistryLayerLive),
  Layer.provideMerge(VcsProvisioningService.layer.pipe(Layer.provide(VcsDriverRegistryLayerLive))),
  Layer.provideMerge(GitWorkflowLayerLive),
  Layer.provideMerge(ReviewLayerLive),
  Layer.provideMerge(SourceControlRepositoryServiceLayerLive),
  Layer.provideMerge(
    VcsStatusBroadcaster.layer.pipe(
      Layer.provide(GitWorkflowLayerLive),
      Layer.provide(
        VcsStatusBroadcaster.autoPullPolicyLayer.pipe(Layer.provide(ServerSettingsLayerLive)),
      ),
    ),
  ),
);
 
const CheckpointingLayerLive = Layer.empty.pipe(
  Layer.provideMerge(CheckpointDiffQuery.layer),
  Layer.provideMerge(CheckpointStore.layer.pipe(Layer.provide(VcsDriverRegistryLayerLive))),
);
 
const PortScannerLayerLive = PortScanner.layer.pipe(Layer.provide(ProcessRunner.layer));
 
const TerminalLayerLive = TerminalManager.layer.pipe(
  Layer.provide(PtyAdapterLive),
  Layer.provide(PortScannerLayerLive),
  Layer.provide(NativeTelemetryLayerLive),
);
 
const PreviewLayerLive = Layer.empty.pipe(
  Layer.provideMerge(PreviewManager.layer),
  Layer.provideMerge(PortScannerLayerLive),
);
 
const DeviceLayerLive = DeviceService.layer.pipe(
  Layer.provide(ServerSettingsLayerLive),
  Layer.provide(ProcessRunner.layer),
  Layer.provide(NetService.layer),
);
 
const WorkspaceEntriesLayerLive = WorkspaceEntries.layer.pipe(Layer.provide(WorkspacePaths.layer));
 
const WorkspaceFileSystemLayerLive = WorkspaceFileSystem.layer.pipe(
  Layer.provide(WorkspacePaths.layer),
  Layer.provide(WorkspaceEntriesLayerLive),
);
 
const WorkspaceLayerLive = Layer.mergeAll(
  WorkspacePaths.layer,
  WorkspaceEntriesLayerLive,
  WorkspaceFileSystemLayerLive,
);
 
const ProjectFaviconResolverLayerLive = ProjectFaviconResolver.layer.pipe(
  Layer.provide(WorkspacePaths.layer),
  Layer.provide(T3ProjectFileLoader.layer),
);
 
const ServerEnvironmentLayerLive = ServerEnvironment.layer.pipe(
  Layer.provide(ServerSecretStore.layer),