feat(ble): expose isInitialized and reclaim memory before radios start

The controller and the WiFi driver each need a large aggregate allocation,
which a live app sitting on garbage can deny - that is why a failed connect
often succeeded on retry. Both bindings now collect before initializing, and
the tree reserves its node and spec capacity so a build does not reallocate
into a tight heap.

native/test/fake_providers.h

@@ -275,9 +275,14 @@ struct Wifi : WifiProvider {
 struct Ble : BleProvider {
   int32_t duration = 0;
   std::string value;
+  bool initialized = false;
 
-  Status init(const std::string*) override { return Status::success(); }
-  void deinit() override {}
+  Status init(const std::string*) override {
+    initialized = true;
+    return Status::success();
+  }
+  void deinit() override { initialized = false; }
+  bool isInitialized() const override { return initialized; }
   Status scan(int32_t durationMs, std::vector<BleDevice>& devices) override {
     duration = durationMs;
     const BleDevice device = {"tag", "aa:bb", -60};

native/test/runtime_test.cpp

@@ -96,7 +96,10 @@ int main() {
              "assert(wifi.connect())");
   assert(bench.wifi.savedReconnect);
 
-  run(state, "assert(ble.scan()[1].address == 'aa:bb')\n"
+  run(state, "assert(not ble.isInitialized())\n"
+             "assert(ble.init())\n"
+             "assert(ble.isInitialized())\n"
+             "assert(ble.scan()[1].address == 'aa:bb')\n"
              "assert(#ble.read('svc', 'chr') == 3)\n"
              "assert(ble.write('svc', 'chr', 'x\\0y'))");
   assert(bench.ble.duration == 3000);