Add typed serial settings operations

Route bounded admin mutations through the existing administration
dispatcher,
covering apply, lifecycle, persistence, authorization, and result
tracking.
Add the browser controls, automatic result refresh, regression coverage,
and
phase documentation.

tests/admin_console_boundary/test.c

@@ -313,5 +313,32 @@ int main(void)
     assert(!lock_depth);
     test_currentness();
     test_dispatch_currentness();
+    unsigned before_serial = runs;
+    assert(admin_ssh_console_submit_serial_settings(0) == ESP_ERR_INVALID_STATE);
+    s_dispatch_ready = false;
+    assert(admin_ssh_console_submit_serial_settings(1) == ESP_ERR_INVALID_STATE);
+    s_dispatch_ready = true; queue_full = true;
+    assert(admin_ssh_console_submit_serial_settings(1) == ESP_ERR_TIMEOUT);
+    queue_full = false;
+    admin_request_t preceding_uart = {.origin = ADMIN_REQUEST_UART0};
+    assert(xQueueSend(s_request_queue, &preceding_uart, 0));
+    queue_send_wait = portMAX_DELAY;
+    assert(admin_ssh_console_submit_serial_settings(17) == ESP_OK && !serial_settings_executed);
+    assert(queue_send_wait == 0);
+    admin_request_t typed;
+    memcpy(&typed, s_request_queue->bytes + sizeof(typed), sizeof(typed));
+    assert(typed.origin == ADMIN_REQUEST_SERIAL_SETTINGS && typed.serial_settings_id == 17);
+    assert(s_request_queue->capacity == 4 && sizeof(typed.line) == 257);
+    pump(worker_task);
+    assert(serial_settings_executed == 17 && runs == before_serial + 1 && !s_request_queue->count);
+    assert(serial_settings_preceding_runs == before_serial + 1);
+    for (unsigned i = 0; i < s_request_queue->capacity; ++i)
+        assert(xQueueSend(s_request_queue, &preceding_uart, 0));
+    queue_send_wait = portMAX_DELAY;
+    assert(admin_ssh_console_submit_serial_settings(18) == ESP_ERR_TIMEOUT);
+    assert(queue_send_wait == 0 && s_request_queue->count == 4 && serial_settings_executed == 17);
+    pump(worker_task);
+    assert(runs == before_serial + 5 && serial_settings_executed == 17 && !s_request_queue->count);
+    puts("PASS: typed Serial admission uses zero wait on success/full queue, preserves all four queued UART requests and FIFO execution, no command-string dispatch");
     puts("PASS: admission/identity, two owners, completion contention/reopen, history, queued stale/revoked work, UART dispatch, hidden/disconnected prompts, exit-to-SELF_CLOSE, deferred rejection/drain/close, 5s output backpressure");
 }