Refactor middleware

[ScriptSmith]

No description provided.

[greptile-apps]

Greptile Summary

Reorganized middleware module structure by creating two subdirectories: layers/ for actual Axum middleware and util/ for internal helper functions.

Key changes:

• Moved 6 middleware layers into src/middleware/layers/: admin, api (renamed from combined), authz, rate_limit, request_id, security_headers
• Moved 3 internal utilities into src/middleware/util/: budget, scope, usage
• Updated all import paths throughout the affected files to reflect new structure
• Maintained all public exports from middleware/mod.rs, ensuring no breaking changes for consumers
• Improved naming: combined.rs → api.rs for better semantic clarity

Review findings:

• All import path updates are correct and consistent
• Module visibility (pub(crate)) is appropriately maintained
• No logic changes, purely structural refactoring
• Public API surface remains unchanged

Confidence Score: 5/5

• This PR is safe to merge with no risk
• This is a pure refactoring that only reorganizes file structure and updates import paths. No logic changes were made, all public exports are maintained, and all import path updates are correct and consistent. The refactoring improves code organization without introducing any behavioral changes or breaking the public API.
• No files require special attention

Important Files Changed

Filename	Overview
src/middleware/layers/api.rs	Renamed from combined.rs to api.rs, updated imports to reference new util module structure
src/middleware/layers/mod.rs	New module file that exports all middleware layers (admin, api, authz, rate_limit, request_id, security_headers)
src/middleware/mod.rs	Updated module structure to organize middleware into layers and util subdirectories, maintained all public exports
src/middleware/util/mod.rs	New module file that exports utility helpers (budget, scope, usage)

_{Last reviewed commit: b6b9411}