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.

tests/admin_console_boundary/adapter.c

@@ -0,0 +1,35 @@
+
+#define SSH_TRANSPORT_MAX_SESSIONS 2U
+typedef struct { bool active, tx_pending; uint32_t session_id, generation; } ssh_transport_session_snapshot_t;
+static ssh_transport_session_snapshot_t s_session_snapshots[2];
+static unsigned stopped, disconnected, rotated, reset, restarted;
+static esp_err_t ssh_transport_stop(void) { ++stopped; return ESP_OK; }
+static esp_err_t ssh_transport_disconnect(uint32_t id) { disconnected=id; return ESP_OK; }
+static esp_err_t ssh_transport_replace_host_key(bool r) { if(r) ++reset; else ++rotated; return ESP_OK; }
+static void esp_restart(void) { ++restarted; }
+static bool admin_console_drained(const admin_ssh_console_token_t *);
+static esp_err_t admin_console_perform(const admin_ssh_console_token_t *, admin_ssh_deferred_action_type_t, uint32_t);
+static void test_adapter(void)
+{
+    admin_ssh_console_token_t token={ .slot_index=0, .session_id=7, .slot_generation=3 };
+    user_principal_t admin={ .role=USER_ROLE_ADMIN };
+    assert(admin_ssh_console_init()==ESP_OK);
+    assert(admin_ssh_console_start_uart_frontend()==ESP_OK);
+    assert(admin_ssh_console_open(&token,&admin)==ESP_OK);
+    assert(!admin_console_drained(&token));
+    s_session_snapshots[0]=(ssh_transport_session_snapshot_t){ .active=true, .session_id=7, .generation=3 };
+    assert(admin_console_drained(&token));
+    token.transport=1; assert(!admin_console_drained(&token));
+    assert(admin_ssh_console_open(&token,&admin)==ESP_ERR_INVALID_ARG);
+    token.transport=0; token.slot_generation=4; assert(!admin_console_drained(&token));
+    assert(admin_console_perform(&token,ADMIN_SSH_DEFER_STOP,0)==ESP_ERR_NOT_FOUND && stopped==0);
+    token.slot_generation=3; s_session_snapshots[0].tx_pending=true;
+    assert(!admin_console_drained(&token)); s_session_snapshots[0].tx_pending=false;
+    assert(admin_console_perform(&token,ADMIN_CONSOLE_DEFER_SELF_CLOSE,99)==ESP_OK && disconnected==7);
+    assert(admin_console_perform(&token,ADMIN_SSH_DEFER_DISCONNECT,99)==ESP_OK && disconnected==99);
+    assert(admin_console_perform(&token,ADMIN_SSH_DEFER_STOP,0)==ESP_OK && stopped==1);
+    assert(admin_console_perform(&token,ADMIN_SSH_DEFER_HOST_KEY_ROTATE,0)==ESP_OK && rotated==1);
+    assert(admin_console_perform(&token,ADMIN_SSH_DEFER_HOST_KEY_RESET,0)==ESP_OK && reset==1);
+    assert(admin_console_perform(&token,ADMIN_SSH_DEFER_REBOOT,0)==ESP_OK && restarted==1);
+    puts("PASS: actual SSH adapter identity/drain checks, legacy admission and lifecycle action routing");
+}