feat: add managed SSH execution spaces

Add managed SSH Hosts and projects with signed side-by-side GoodBuddy Agent and OpenCode Runtime installation, Ask and Execute workspace access, a Main-owned model bridge, detached Agent lifecycle, durable ACP output recovery, and project activation UI.

Use protocol v2 with bounded FIFO frames over SSH instead of custom credit, priority, batching, or model-message chunking. Mismatched Host Agents now upgrade automatically, an exactly verified Node runtime is reused on-host, and local Portable builds can embed strictly verified Agent artifacts.

Release note: 新增托管 SSH 远程项目，可自动安装或升级签名 Agent/OpenCode Runtime，并在 SSH 断线后继续 Agent 工作和同步未确认输出。

src/main/agent/remote-runtime-channel.ts

@@ -0,0 +1,153 @@
+import type {
+  AcpBindingCursors,
+  AcpCompletePromptRequest,
+  AcpCompletePromptResult,
+  AcpEscalateCancellationRequest,
+  AcpReconcilePromptRequest,
+  AcpReconcilePromptResult
+} from '../../shared/agent-protocol'
+import type {
+  RemotePromptOperationAcceptance,
+  RemotePromptOperationPreparation,
+} from '../../shared/remote-agent-contracts'
+import type {
+  ModelBridgePolicy
+} from '../../shared/model-bridge-contracts'
+
+export type RemoteRuntimeChannelCapabilities = {
+  cancellationEscalation: boolean
+  promptOperationReconciliation: boolean
+  modelBridge?: boolean
+}
+
+export type RuntimeSessionBindingCursors = AcpBindingCursors
+
+export type RemoteCancellationEscalation = Omit<
+  AcpEscalateCancellationRequest,
+  'reason'
+> & {
+  reason: unknown
+}
+
+export type RemotePromptOperationReconciliation =
+  AcpReconcilePromptRequest
+
+export type RemotePromptOperationReconciliationResult =
+  AcpReconcilePromptResult
+export type RemotePromptOperationCompletion = AcpCompletePromptRequest
+export type RemotePromptOperationCompletionResult =
+  AcpCompletePromptResult
+
+export type RemoteModelBridgeOpenRequest = {
+  bindingId: string
+  promptOperationId: string
+  requestId: string
+  policy: ModelBridgePolicy
+}
+
+export type RemoteModelBridgeCloseResult = {
+  clean: boolean
+  poisoned: boolean
+}
+
+export interface RemoteModelBridgeSession {
+  readonly version: 'goodbuddy-model-bridge-v1'
+  readonly channelId: string
+  readonly channelEpoch: string
+  readonly policy: ModelBridgePolicy
+  readonly closed: Promise<RemoteModelBridgeCloseResult>
+  close(reason?: string): Promise<RemoteModelBridgeCloseResult>
+}
+
+/**
+ * A process-neutral, already authenticated ACP virtual channel.
+ *
+ * Implementations own framing, journaling and transport generation checks.
+ * The runtime intentionally receives no SSH client, socket or command API.
+ */
+export interface RemoteRuntimeChannel {
+  readonly input: ReadableStream<Uint8Array>
+  readonly output: WritableStream<Uint8Array>
+  readonly generation: number
+  readonly channelEpoch: string
+  /**
+   * Signed Runtime capability identity advertised by the Agent before the
+   * untrusted Runtime process starts.
+   */
+  readonly advertisedAcpCapabilitiesDigest: string
+  readonly capabilities: RemoteRuntimeChannelCapabilities
+  readonly closed: Promise<void>
+
+  isCurrentGeneration(): boolean
+  getBindingCursors(
+    bindingId: string
+  ): Promise<RuntimeSessionBindingCursors>
+  /** Accepts the prompt and starts its Ask or Execute Runtime process. */
+  preparePrompt(
+    preparation: RemotePromptOperationPreparation
+  ): Promise<RemotePromptOperationAcceptance>
+  /**
+   * Bounds same-daemon stream recovery to the signed prompt lifetime and
+   * caller cancellation. Implementations that cannot recover may omit it.
+   */
+  setRecoveryBoundary?(
+    deadlineAt: string,
+    signal: AbortSignal
+  ): void
+  clearRecoveryBoundary?(): void
+  /**
+   * Allocates and registers a fresh Main-owned model channel for one prompt.
+   * Legacy channels may omit this when the runtime is configured without a
+   * model bridge.
+   */
+  openModelBridge?(
+    request: RemoteModelBridgeOpenRequest
+  ): Promise<RemoteModelBridgeSession>
+  completePromptOperation(
+    operation: RemotePromptOperationCompletion
+  ): Promise<RemotePromptOperationCompletionResult>
+  /**
+   * Stops or resumes inbound ACP delivery. Pausing must take effect before
+   * the returned promise resolves and must not advance the Main ACK cursor.
+   */
+  setInboundPaused(paused: boolean): Promise<void>
+  escalateCancellation(
+    escalation: RemoteCancellationEscalation
+  ): Promise<void>
+  reconcilePromptOperation(
+    operation: RemotePromptOperationReconciliation
+  ): Promise<RemotePromptOperationReconciliationResult>
+  close(): Promise<void>
+}
+
+export class StaleRemoteRuntimeGenerationError extends Error {
+  constructor() {
+    super('远端 Runtime 连接代际已失效')
+    this.name = 'StaleRemoteRuntimeGenerationError'
+  }
+}
+
+export function isDefinitiveRemoteRuntimeRequestRejection(
+  error: unknown,
+  method: string
+): boolean {
+  if (
+    error === null ||
+    typeof error !== 'object' ||
+    !('remoteRequestOutcome' in error) ||
+    error.remoteRequestOutcome !== 'rejected' ||
+    !('remoteMethod' in error) ||
+    error.remoteMethod !== method
+  ) {
+    return false
+  }
+  return true
+}
+
+export function assertCurrentRemoteRuntimeGeneration(
+  channel: RemoteRuntimeChannel
+): void {
+  if (!channel.isCurrentGeneration()) {
+    throw new StaleRemoteRuntimeGenerationError()
+  }
+}