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/include/lua/providers.h

@@ -231,6 +231,7 @@ public:
   virtual ~BleProvider() = default;
   virtual Status init(const std::string* name) = 0;
   virtual void deinit() = 0;
+  virtual bool isInitialized() const = 0;
   virtual Status scan(int32_t durationMs, std::vector<BleDevice>& devices) = 0;
   virtual Status connect(const std::string& address) = 0;
   virtual void disconnect() = 0;