Add SSH Console Ownership Boundary (Phase 8D.4)

Implement transport-qualified session identity and immutable owner
adapters
for SSH console lifecycle and output-drain operations. Add focused host
tests
covering admission, stale identities, deferred actions, completion
races,
prompts, backpressure, and slot reuse. Update Phase 8D documentation and
current-state tracking.

docs/agent/code-map.md

@@ -110,6 +110,7 @@ This is a semantic map, not a complete file inventory. Start here, then read the
 - Ownership: dispatcher is sole `esp_console_run()` caller; the SSH owner exclusively performs post-initialization wolfSSH runtime calls.
 - Lifecycle: remote session tokens include slot generation; fixed output/history/prompt state is wiped immediately on idle close or after an executing handler returns. Admin SSH `exit` and Ctrl+D on an empty command line request bounded deferred self-disconnect after best-effort output draining.
 - Constraint: one slow command or prompt serializes all administration. Admin SSH is unavailable until command registration and UART frontend creation complete; supported deferred actions wait only for a bounded application-buffer drain heuristic.
+- 8D.4 boundary: `admin_ssh_console_open_owned()` copies transport-qualified identity and retains an immutable firmware-lifetime drain/lifecycle adapter; the existing two slots are shared. SSH compatibility admission/adapter resides in `ssh_transport.c`; no browser admin caller yet. Owners handle liveness/output; completion scratch is nonblockingly serialized. Focused host command: `python3 tests/admin_console_boundary/run.py`.
 
 ## Wi-Fi