fix: DispatchResult memory leak and remove dead code

- Fix DispatchResult::run() leaking the wrapper (was using mem::forget
  instead of letting Drop clean up)
- Remove unused UberDispatcher::as_raw() method
- Add compile-time static_assert for FrontendChannel BASE size

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: bartlomieju

src/crdtp.rs

@@ -496,7 +496,7 @@ impl DispatchResult {
     unsafe {
       crdtp__DispatchResult__Run(self.ptr);
     }
-    std::mem::forget(self);
+    // Drop will call crdtp__DispatchResult__DELETE to free the wrapper.
   }
 }
 
@@ -530,10 +530,6 @@ impl UberDispatcher {
     }
   }
 
-  /// Get the raw pointer for passing to C++ Wire functions.
-  pub fn as_raw(&mut self) -> *mut Self {
-    self as *mut Self
-  }
 }
 
 impl Drop for UberDispatcher {

src/crdtp_binding.cc

@@ -43,6 +43,9 @@ struct crdtp__FrontendChannel__BASE : public FrontendChannel {
   }
 };
 
+static_assert(sizeof(crdtp__FrontendChannel__BASE) <= sizeof(void*),
+              "FrontendChannel BASE must fit in a single vtable pointer");
+
 extern "C" {
 
 void crdtp__FrontendChannel__BASE__CONSTRUCT(