Use cacheMaxMemorySize config in default cache handler (#85153)
### What?
This refactoring enables the `cacheMaxMemorySize` configuration option
to control the memory limits of the default "use cache" handler.
### Why?
Previously, the default cache handler was hardcoded to use 50MB of
memory, ignoring the user's `cacheMaxMemorySize` configuration. This
meant users couldn't:
- Disable internal caching when using external CDNs (by setting size to
0)
- Customize memory limits based on their deployment environment
- Control memory usage for the "use cache" handler
### How?
- Extracted cache handler creation into `createDefaultCacheHandler()`
factory function
- Threaded `cacheMaxMemorySize` through `initializeCacheHandlers()`
calls
- Harmonized parameter naming (`maxMemoryCacheSize` →
`cacheMaxMemorySize`) for consistency with the config
- Made `cacheMaxMemorySize` required in type signatures
- Added zero-size optimization (returns no-op handler when size=0)
