Merge updated rfc/pty into feature/persistent-pty-sessions

# Conflicts:
#	docs/architecture.i18n.yaml
#	docs/core-data-structures/core.md
#	pnpm-lock.yaml
#	scripts/gen-cordis-catalog.ts

docs/core-data-structures/bash.md

@@ -67,8 +67,8 @@ interface BashExecRequest {
    * reject non-`DSH_*` names supplied through this managed channel.
    */
   dshEnv?: DshEnvironment | undefined
-  /** Explicit per-call sandbox mode override. */
-  sandboxMode?: SandboxMode | undefined
+  /** Fully resolved per-call sandbox policy; sandboxing executors default it. */
+  sandboxPolicy?: SandboxExecutionPolicy | undefined
 }
 ```
 
@@ -100,8 +100,8 @@ interface BashExecSpec {
   env?: Record<string, string> | undefined
   /** Managed `DSH_*` snapshot; implementations reject ordinary names. */
   dshEnv?: DshEnvironment | undefined
-  /** Resolved sandbox mode; ignored by executors that do not confine. */
-  sandboxMode: SandboxMode | undefined
+  /** Resolved sandbox policy; ignored by executors that do not confine. */
+  sandboxPolicy: SandboxExecutionPolicy | undefined
 }
 ```
 
@@ -159,7 +159,7 @@ interface CollectedOutput {
 
 ## File sandbox: `BashSandboxInfo`
 
-A sandbox-consuming executor exposes its configured fallback through `BashExecutor.sandboxMode`. The tool layer folds each session's durable `sandbox/mode` override (owned by [`@deepseek-ai/dsh-sandbox-policy`](../../packages/sandbox/sandbox-policy/README.md)) and may replace it for one user-approved strictly wider call. The mode/enforcement vocabulary is owned by the [`@deepseek-ai/dsh-sandbox` seam](sandbox.md); modes govern file effects only.
+A sandbox-consuming executor exposes its configured mode fallback through `BashExecutor.sandboxMode`. The tool layer asks [`@deepseek-ai/dsh-sandbox-policy`](../../packages/sandbox/sandbox-policy/README.md) to resolve each calling session's durable `sandbox/mode` override and immutable cwd into `BashExecRequest.sandboxPolicy`; a user-approved strictly wider call replaces only the mode. The mode/root/enforcement vocabulary is owned by the [`@deepseek-ai/dsh-sandbox` seam](sandbox.md); modes govern file effects only.
 
 A sandboxed run reports its mode, conservative denial classification, and enforcement completeness. `runnerFailed` marks a sandbox runner failure before the command ran; foreground execution throws `SANDBOX_UNAVAILABLE`, while a settled background process has only its facts channel.
 

docs/core-data-structures/core.md

@@ -30,7 +30,7 @@ Everything else is documented on a **sub-page**, not here. The rule that draws t
 | [approval.md](approval.md) | the one-shot user-approval seam: `ApprovalRequest`, `ApprovalOutcome`, per-session policy, audit and answerer contracts |
 | [bash.md](bash.md) | the bash executor seam: `BashExecRequest`/`Spec`, `BashRunResult`, background `BashProcess` handles |
 | [pty.md](pty.md) | persistent terminal ids, backend/session contracts, send readiness, bounded reads, and owner-visible snapshots |
-| [sandbox.md](sandbox.md) | the process-confinement seam: file-effect modes, `SandboxPolicy`, `ConfinedArgv`, enforcement and fail-closed errors |
+| [sandbox.md](sandbox.md) | per-session policy resolution and the process-confinement seam: file-effect modes, execution/provider policies, `ConfinedArgv`, enforcement and fail-closed errors |
 | [code-runtime.md](code-runtime.md) | the code-execution seam: `CodeRunRequest`/`Result`, binding namespaces, captured logs, the `CodeRunFailure` taxonomy |
 | [filesystem.md](filesystem.md) | the filesystem seam: `FsTarget`, read/write/edit outcomes, observed-file state, `FsErrorCode` |
 | [lsp.md](lsp.md) | the LSP navigation seam: `LspQueryRequest`/`Result`, `LspProvider`/`Service`, four operations, `LspError` |

docs/core-data-structures/sandbox.md

@@ -38,7 +38,35 @@ type SandboxEnforcement = 'full' | 'partial'
 
 ## Per-call policy
 
-The policy is fully resolved and carried per call. This permits concurrent consumers and one-shot escalated retries to ask the same provider for different boundaries without mutating provider state.
+The complete execution policy is resolved and carried per capability call. It includes `danger-full-access` so a consumer can resolve policy once before deciding whether to bypass confinement. Normal tool calls derive `workspaceRoot` from the calling session's immutable cwd; deployment configuration is the agentless fallback. The root is canonicalized with filesystem semantics before lexical normalization, so a cwd containing `symlink/..` identifies the directory where a spawned process actually runs.
+
+```ts type-equiv
+/**
+ * The complete file-effect policy resolved for one capability call. The root
+ * is carried even under modes that do not consume it so callers can resolve
+ * policy once before choosing the enforcement path.
+ */
+interface SandboxExecutionPolicy {
+  /** The file-effect mode this execution runs under. */
+  mode: SandboxMode
+  /** Absolute root directory `workspace-write` may write under. */
+  workspaceRoot: string
+}
+```
+
+`ctx.sandboxPolicy.resolve()` accepts the active session and, for an approved retry, an explicit mode. The service owns precedence and root fallback so bash and fs do not repeat it.
+
+```ts type-equiv
+/** Inputs that select the sandbox policy for one capability call. */
+interface SandboxPolicyRequest {
+  /** Calling session; its immutable cwd becomes the workspace boundary. */
+  session?: Session
+  /** Explicit approved mode override, which outranks session policy. */
+  mode?: SandboxMode
+}
+```
+
+Only a confined execution reaches `ctx.sandbox`; its provider policy narrows the mode while retaining the same root. This permits concurrent sessions, consumers, and one-shot escalated retries to ask the same provider for different boundaries without mutating provider state.
 
 ```ts type-equiv
 /**
@@ -46,15 +74,12 @@ The policy is fully resolved and carried per call. This permits concurrent consu
  * fixed on the provider: two consumers may confine under different policies
  * at the same instant (bash under `read-only` while a confined child agent
  * needs its state directory writable), and an approved escalated retry is a
- * new call with a wider policy. Defaulting/resolution is the consumer's
- * explicit step (its config owns the fallback chain); the provider treats
- * the policy as fully specified.
+ * new call with a wider policy. Defaulting/resolution is an explicit step at
+ * the consumer boundary; the provider treats the policy as fully specified.
  */
-interface SandboxPolicy {
+interface SandboxPolicy extends SandboxExecutionPolicy {
   /** The file-effect mode this execution runs under. */
   mode: ConfinedSandboxMode
-  /** Absolute root directory `workspace-write` may write under. */
-  workspaceRoot: string
 }
 ```