Inline register_type_data to cut down on binary size (#22030)

# Objective

My [TypeData dependencies](#22016 ) PR regressed native binary size by
~8mb.

(thank you [twitcher](https://github.com/bevyengine/twitcher/))

<img width="858" height="306" alt="image"
src="https://github.com/user-attachments/assets/e6d86c67-33f6-4280-bee4-49771014b678"
/>

## Solution

- Inline `register_type_data`, which restores the original binary size:
  - `release breakout` before #22016: 127.3mb
  - `release breakout` after #22016: 136.4mb
  - `release breakout` after this PR: 127.4mb

Author: cart

crates/bevy_reflect/src/type_registry.rs

@@ -590,6 +590,7 @@ impl TypeRegistration {
 
     /// Inserts the [`TypeData`] instance of `T` created for `V`, and inserts any
     /// [`TypeData`] dependencies for that combination of `T` and `V`.
+    #[inline]
     pub fn register_type_data<T: TypeData + FromType<V>, V>(&mut self) {
         self.insert(T::from_type());
         T::insert_dependencies(self);