feat(types): brand bash ids + stop brand erosion; extract Branded to dsh-brand

Type-only change (brands are zero-cost casts; no runtime/wire impact). Closes
the two gaps in the "brand ids that cross package boundaries" policy and fixes
the dependency direction so a capability package never pulls in an unrelated one.

- Extract the `Branded<B>` primitive into a new standalone type-only package
  `@deepseek-ai/dsh-brand` (packages/util/brand) with no harness-package deps.
  dsh-llm keeps its owned CallId but imports Branded from dsh-brand; dsh-session,
  dsh-agent, and dsh-bash all import Branded from there. dsh-bash depends on
  dsh-brand ALONE — never on dsh-llm or dsh-session (the architectural fix: a
  generic execution backend must not couple to the LLM or session vocabulary).
- Mint BashTaskId + OwnerToken in dsh-bash and thread them through BashTask.id,
  the get/ownerOf/list/readOutput/kill seam, the bash-local generation site, and
  the dsh-tool-bash validate/access surface. OwnerToken is a DISTINCT brand from
  SessionId so the seam stays decoupled; dsh-tool-bash is the single boundary
  that casts SessionId -> OwnerToken.
- Brand at the SOURCE, not via mid-pipeline casts: agent-loop's Config types
  agents[].id as AgentId and resumeSessionId as SessionId, so the brand enters
  at the config boundary and the inner create()/resume casts disappear (only the
  genuinely-new per-run session-id string is cast).
- Stop brand erosion: propagate CallId/SessionId/AgentId to the registry/store
  Map keys and public params/exports (SessionStore, AgentRegistry + factory
  options, the ACP session-id surface + ToolPresenter CallId map, the
  persistence coordinator, invariants pendingCalls, the pi-ai tool-call maps).
- Docs: document BashTaskId/OwnerToken in bash.md (type-equiv re-pasted), point
  the Branded type-equiv at dsh-brand, fix stale param types in the session/
  agent/bash READMEs, regenerate the cordis catalog + module graph.

Implements docs/rfc/proposed/architecture/2026-06-20-branded-ids.md

packages/core/agent-loop/tests/coverage-edges.spec.ts

@@ -4,7 +4,7 @@ import LlmService, { CallId, LlmError, StreamChunk } from '@deepseek-ai/dsh-llm'
 import SessionStore, { TurnEndReason } from '@deepseek-ai/dsh-session'
 import SystemPrompt from '@deepseek-ai/dsh-system-prompt'
 import ToolRegistry, { defineTool } from '@deepseek-ai/dsh-tools'
-import AgentRegistry from '@deepseek-ai/dsh-agent'
+import AgentRegistry, { AgentId } from '@deepseek-ai/dsh-agent'
 import AgentLoop, { ReactLoopAgent } from '@deepseek-ai/dsh-agent-loop'
 import { MockAdapter, textResponse, toolCallResponse } from './mock-adapter.ts'
 
@@ -43,7 +43,7 @@ describe('turn boundary listener throws (handled in-turn, loop survives)', () =>
     // The second turn should proceed normally and consume the first script entry.
     const adapter = new MockAdapter([textResponse('turn 2')])
     const ctx = await harness(adapter)
-    const agent = ctx.agentLoop.create('a1', { model: 'mock' })
+    const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
     let threwOnce = false
     ctx.on('agent/turn-start', () => {
@@ -73,7 +73,7 @@ describe('turn boundary listener throws (handled in-turn, loop survives)', () =>
   it('a throwing agent/turn-end listener surfaces via agent/error and the loop survives', async () => {
     const adapter = new MockAdapter([textResponse('turn 1'), textResponse('turn 2')])
     const ctx = await harness(adapter)
-    const agent = ctx.agentLoop.create('a1', { model: 'mock' })
+    const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
     let threwOnce = false
     ctx.on('agent/turn-end', () => {
@@ -107,7 +107,7 @@ describe('turn boundary listener throws (handled in-turn, loop survives)', () =>
     // driver survives. This is the ONLY path that reaches the backstop.
     const adapter = new MockAdapter([textResponse('turn 2')])
     const ctx = await harness(adapter)
-    const agent = ctx.agentLoop.create('a1', { model: 'mock' })
+    const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
     const errors: { turn: number; step: number; message: string }[] = []
     ctx.on('agent/error', (_a, turn, step, error) => void errors.push({ turn, step, message: error.message }))
@@ -149,7 +149,7 @@ describe('tool JSON parse', () => {
         return [{ type: 'text', text: typeof args === 'string' ? `raw: ${args}` : JSON.stringify(args) }]
       },
     }))
-    const agent = ctx.agentLoop.create('a1', { model: 'mock' })
+    const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
     send(agent, 'use tool')
     await waitForIdle(ctx, agent)
@@ -182,7 +182,7 @@ describe('tool JSON parse', () => {
         return [{ type: 'text', text: 'ran with empty args' }]
       },
     }))
-    const agent = ctx.agentLoop.create('a1', { model: 'mock' })
+    const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
     send(agent, 'use tool')
     await waitForIdle(ctx, agent)
@@ -195,7 +195,7 @@ describe('toError normalization', () => {
   it('normalizes non-Error throws from turn-start listeners via toError', async () => {
     const adapter = new MockAdapter([textResponse('ok')])
     const ctx = await harness(adapter)
-    const agent = ctx.agentLoop.create('a1', { model: 'mock' })
+    const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
     let threwOnce = false
     ctx.on('agent/turn-start', () => {
@@ -221,7 +221,7 @@ describe('toError normalization', () => {
   it('normalizes non-Error throws from agent/request waterfall via inline toError in runStep catch', async () => {
     const adapter = new MockAdapter([textResponse('irrelevant')])
     const ctx = await harness(adapter)
-    const agent = ctx.agentLoop.create('a1', { model: 'mock' })
+    const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
     let threwOnce = false
     ctx.on('agent/request', async (_agent, _turn, _step, _options, _next) => {
@@ -249,7 +249,7 @@ describe('coded error data emission', () => {
   it('errorData includes code when a coded error (LlmError) is thrown from a plugin', async () => {
     const adapter = new MockAdapter([textResponse('turn 1')])
     const ctx = await harness(adapter)
-    const agent = ctx.agentLoop.create('a1', { model: 'mock' })
+    const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
     let threwOnce = false
     ctx.on('agent/request', async (_agent, _turn, _step, _options, next) => {
@@ -283,7 +283,7 @@ describe('disposed vs aborted branching', () => {
     const ctx = await harness(adapter)
     let agent!: ReactLoopAgent
     const fiber = await ctx.plugin(Object.assign((inner: Context) => {
-      agent = inner.agentLoop.create('scoped', { model: 'mock' })
+      agent = inner.agentLoop.create(AgentId('scoped'), { model: 'mock' })
     }, { inject: ['agentLoop'] }))
 
     const reasons: TurnEndReason[] = []
@@ -311,7 +311,7 @@ describe('structured tool error propagation (the runtime-validation RFC, part 2)
       textResponse('done'),
     ])
     const ctx = await harness(adapter)
-    const agent = ctx.agentLoop.create('a1', { model: 'mock' })
+    const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
     ctx.tools.register(defineTool({
       name: 'boom',
       description: 'always fails',