Add Response.raise_for_excepted_status() method

[KimBioInfoStudio]

Summary

Add a new Response.raise_for_excepted_status(expected) method that provides strict status code validation. Unlike raise_for_status() which only raises on non-2xx status codes, this method requires all acceptable status codes to be explicitly listed—including success codes.

Use case: In some API integrations, certain non-2xx status codes are expected (e.g., 404 when checking resource existence). Conversely, you may want to ensure only specific status codes are accepted.

response.raise_for_excepted_status([200, 404])  # Only 200 and 404 allowed

Changes

• Add _ensure_request() helper to validate request is set
• Add _raise_status_error() helper to build and raise HTTPStatusError
• Refactor raise_for_status() to use shared helpers
• Add raise_for_excepted_status() with strict status code validation
• Add documentation in api.md and quickstart.md
• Add comprehensive unit tests (10 test cases)

Checklist

• I understand that this PR may be closed in case there was no previous discussion.
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.