<!-- Add the related story/sub-task/bug number, like Resolves#123, or
remove if NA -->
**Related issue:** Resolves#37092
# Checklist for submitter
If some of the following don't apply, delete the relevant line.
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
## Testing
- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **New Features**
* Added per‑IP rate limiting to IdP metadata and SSO endpoints.
* Implemented TTL-backed in‑memory caching for IdP metadata responses to
reduce backend load.
* **Tests**
* Added tests covering metadata caching behavior, cache miss/error
handling, and content type preservation.
* Added tests validating rate limiting behavior across clients, bursts,
and proxy scenarios.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
<!-- Add the related story/sub-task/bug number, like Resolves#123, or
remove if NA -->
**Related issue:** Resolves#40028
# Checklist for submitter
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
## Testing
- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
## Release Notes
* **Bug Fixes**
* Fixed telemetry misclassification where client-side errors were
incorrectly reported as server errors. Client-side errors and request
cancellations are now properly categorized for improved error tracking
and observability.
* **Tests**
* Added test coverage for client error detection and context
cancellation handling.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
<!-- Add the related story/sub-task/bug number, like Resolves#123, or
remove if NA -->
**Related issue:** Resolves#38889
Also delete the unnecessary logging.DiscardHandler and replace it with
slog.DiscardHandler
# Checklist for submitter
If some of the following don't apply, delete the relevant line.
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
- Changes file already present from previous PR
## Testing
- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
* **Chores**
* Modernized internal logging infrastructure by transitioning from a
custom logging implementation to the standard library's structured
logging approach across multiple services and middleware components.
* **Refactor**
* Updated logging method signatures and error handling paths to use
standardized logging interfaces consistently throughout the platform
codebase.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
<!-- Add the related story/sub-task/bug number, like Resolves#123, or
remove if NA -->
**Related issue:** Resolves#37192
- Move /server/service/middleware/endpoint_utils to
/server/platform/endpointer
- Move /server/service/middleware/authzcheck to
/server/platform/middleware/authzcheck
- Move /server/service/middleware/ratelimit to
/server/platform/middleware/ratelimit
# Checklist for submitter
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
## Testing
- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
## Release Notes
* **Refactor**
* Reorganized internal endpoint utilities to a centralized platform
location for improved code organization and maintainability. No
functional changes to existing features or APIs.
<sub>✏️ Tip: You can customize this high-level summary in your review
settings.</sub>
<!-- end of auto-generated comment: release notes by coderabbit.ai -->