DSH: bridge ACP sessions to durable Cindy bindings

## 目标

通过 Main-owned `DshBridgePort` 创建、恢复和跟随 ACP session，并持久化安全的 Cindy binding/cursor。

## 交付

- maker-core DshAgent 与 typed command/receipt/envelope port；Main owns ACP stdio/SSH forward。
- append-only `dsh_session_bindings` migration/repository；仅保存 opaque runtime id、scope、release/capability fingerprint、cursor 和 lifecycle。
- receipt-first reconciliation、sequence dedupe、history gap、uncertain prompt never replay。

## 验收

- 一个 runtime session 只有一个 bridge owner；多 account/scope/session 不串线。
- 不存 endpoint/token/profile/raw DSH log，不读取私有状态。

Blocked by #3773. Blocks #3775.

Canonical plan: `docs/issues/dsh-native-integration/`.

Start with docs/issues/dsh-native-integration/ and the dependency issue #3773, then trace the maker-core DshAgent and Main-owned DshBridgePort entry points named in the issue. Review the proposed dsh_session_bindings migration/repository and define completion against the stated acceptance criteria: single ownership, scoped isolation, receipt-first reconciliation, and no private endpoint, token, profile, or raw-log storage.

Written by the indexing model from the issue text.