* refactor: use base::circular_deque in ResolveProxyHelper
* refactor: use base::circular_deque in GetExtraCrashKeys()
refactor: reduce visibility of kMaxCrashKeyValueSize
This change is to match Chromium's usage advice from
base/containers/README.md: `base:circular_deque` is preferred over
`std::deque` to provide consistent performance across platforms.