docs(api): describe Connection-owned transport

AGENTS.md

@@ -118,7 +118,7 @@ Real-API tests and demos read `DEEPSEEK_API_KEY`, optional `DEEPSEEK_BASE_URL`,
 - **Opaque cross-boundary ids are branded** (`Branded<B>` from `dsh-brand`), never bare `string`.
 - **Trust TypeScript at typed same-process boundaries.** Do not add runtime validation, fallback behavior, or hostile-input tests solely for values the static interface requires; validate at parser/config, queued, model/tool JSON, durable/file, worker, process, and wire boundaries.
 - **Source plane vs artifact plane, never mixed.** Static gates and tests resolve workspace imports through tsconfig `paths` to `src` and pass on a clean tree; gates consuming built `lib/` declare that dependency ([layout](docs/development.md#typescript-project-layout)).
-- **Keep compiler faces explicit.** Each package uses one aggregate except `api/remotes`; repo-wide programs seed a face config, never the root solution ([layout](docs/development.md#typescript-project-layout)).
+- **Keep compiler faces explicit.** A package with both Host and Client programs exposes face-specific leaf configs and a solution-only root; repo-wide programs seed a face config, never the root solution ([layout](docs/development.md#typescript-project-layout)).
 - **An empty `catch` names what it swallows** and why nothing else can reach it; keep the `try` to one statement.
 - **Keep comments local.** Do not restate code, explain distant behavior unless locally required, or expand unrelated comments ([rationale](.agents/notes/implemented/process/2026-08-09-concrete-prose-names-actors-and-recorded-facts.md)).
 - **Prefer symmetry for parallel values**; unexplained asymmetry usually signals a missed extraction.