feat(acp): hosts install a managed runtime over RPC, and mark agents whose program Orca provides (#29024)

* feat(acp): hosts install a managed runtime over RPC, and mark agents whose program Orca provides

managedRuntime.status / managedRuntime.install / managedRuntime.cancel, negotiated by
managed-runtime.install.v1, act on the host that receives them, the one that runs the agent's
chats, with no workspace needed. A status read naming the revision it shows is a long-poll on its
own call-queue lane, so every client sees another's start, progress and outcome.
agentSession.agents marks an agent whose program Orca provides on that host.

* fix(runtime): install status says a copy outside Orca's runs only when a start would really run it

* fix(runtime): install status is pushed to subscribers instead of long-polled, and Cancel answers with the outcome

managedRuntime.subscribe {agent} sends a full snapshot on subscribe, then one
snapshot per install state change, and closes with the transport. It replaces
the managedRuntime.status long-poll and its slot registrations.

src/shared/agent-session-registered-agents.ts

@@ -18,6 +18,9 @@ export const AGENT_SESSION_AGENTS_METHOD = 'agentSession.agents'
 export type AgentSessionRegisteredAgent = {
   agent: string
   capabilities: AgentSessionCapabilities
+  /** Orca provides this chat's program on this host, so it needs no installed CLI. Absent from
+   *  older hosts, whose chats are offered only where the agent's CLI was detected. */
+  managedRuntime?: true
 }
 
 export type AgentSessionAgentsResult = {
@@ -46,7 +49,9 @@ const registeredAgentSchema = z.object({
     approvalEnforcement: openEnum(['provider', 'orca'] as const, 'orca')
       .optional()
       .default('orca')
-  })
+  }),
+  // A false from a host reads as absent, so the row keeps the detection-based offer.
+  managedRuntime: z.literal(true).optional().catch(undefined)
 })
 
 /** The host's agents as this build reads them, or null when the reply is not an agent list. */

src/shared/host-operation-ownership.ts

@@ -36,6 +36,7 @@ export const HOST_OPERATION_OWNERSHIP = {
   jira: 'scope-picked',
   layout: 'host',
   linear: 'scope-picked',
+  managedRuntime: 'host',
   managedServer: 'host',
   markdown: 'host',
   mobileRelay: 'host',

src/shared/managed-runtime-install.ts

@@ -1,5 +1,8 @@
 // A runtime Orca installs for an agent only when the person asks, as its host reports it.
 
+// The host answers managedRuntime.subscribe, managedRuntime.install and managedRuntime.cancel.
+export const MANAGED_RUNTIME_INSTALL_RUNTIME_CAPABILITY = 'managed-runtime.install.v1' as const
+
 export type ManagedRuntimeOperation = {
   id: string
   kind: 'install' | 'remove'

src/shared/protocol-version.ts

@@ -62,6 +62,7 @@ export * from './agent-session-resume-runtime-capabilities'
 import { AGENT_SESSION_BACKGROUND_TASK_CHILD_VIEWS_CAPABILITY } from './agent-session-background-task-child-views-capability'
 import { AGENT_SESSION_STOP_RUNTIME_CAPABILITIES } from './agent-session-stop-capabilities'
 import { AGENT_SESSION_CREATE_RUNTIME_CAPABILITIES } from './agent-session-create-capabilities'
+import { MANAGED_RUNTIME_INSTALL_RUNTIME_CAPABILITY } from './managed-runtime-install'
 import { REMOTE_SERVER_UPDATE_CAPABILITY } from './remote-server-update'
 import { MOBILE_RELAY_RUNTIME_CAPABILITIES } from './mobile-desktop-relay-contract'
 import { SKILL_RUNTIME_CAPABILITIES } from './skill-install-capability'
@@ -229,6 +230,7 @@ export const RUNTIME_CAPABILITIES = [
   ...SESSION_TABS_RUNTIME_CAPABILITIES,
   AGENT_SESSION_BOUNDARY_RUNTIME_CAPABILITY,
   REMOTE_SERVER_UPDATE_CAPABILITY,
+  MANAGED_RUNTIME_INSTALL_RUNTIME_CAPABILITY,
   AGENT_SESSION_HOST_AUTHORITY_RUNTIME_CAPABILITY,
   AGENT_SESSION_OMP_RESUME_PATH_RUNTIME_CAPABILITY,
   AGENT_SESSION_KEYBOARD_RUNTIME_CAPABILITY,

src/shared/rpc-contract/managed-runtime-install-params.ts

@@ -0,0 +1,9 @@
+import { z } from 'zod'
+import { StructuredAgent } from './structured-agent-session-params'
+
+export const ManagedRuntimeAgentParams = z.strictObject({ agent: StructuredAgent })
+
+export const ManagedRuntimeCancelParams = z.strictObject({
+  agent: StructuredAgent,
+  operationId: z.string().min(1).max(64)
+})

src/shared/rpc-contract/rpc-params-catalog.generated.ts

@@ -381,6 +381,10 @@ import {
   WorkspaceSelection
 } from './linear-params'
 import { CreateProject } from './linear-project-create-params'
+import {
+  ManagedRuntimeAgentParams,
+  ManagedRuntimeCancelParams
+} from './managed-runtime-install-params'
 import {
   ManagedServerRecover,
   ManagedServerSelector,
@@ -1083,6 +1087,9 @@ export const RPC_PARAMS_BY_METHOD = {
   'linear.teamStates': TeamId,
   'linear.testConnection': WorkspaceSelection,
   'linear.updateIssue': IssueUpdateOfLinearParams,
+  'managedRuntime.cancel': ManagedRuntimeCancelParams,
+  'managedRuntime.install': ManagedRuntimeAgentParams,
+  'managedRuntime.subscribe': ManagedRuntimeAgentParams,
   'managedServer.cancelStop': ManagedServerSelector,
   'managedServer.forget': ManagedServerSelector,
   'managedServer.recover': ManagedServerRecover,