[ROMM-2668] Speedup feeds endpoint

[gantoine]

Description
^{Explain the changes or enhancements you are proposing with this pull request.}

Hoping this doesn't break downloads...

Fixes #2668

Checklist
^{Please check all that apply.}

• I've tested the changes locally
• I've updated relevant comments
• I've assigned reviewers for this PR
• I've added unit tests that cover the changes

[gemini-code-assist]

Summary of Changes

Hello @gantoine, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly improves the performance of various API endpoints, particularly the feeds endpoint, by optimizing how Rom and RomFile data are fetched from the database. By implementing eager loading for associated RomFile objects directly within the Rom query, it eliminates redundant database calls, leading to faster data retrieval and reduced load on the database.

Highlights

• Database Query Optimization: Replaced explicit calls to db_rom_handler.get_rom_files(rom.id) with direct access to rom.files in several API endpoints, including those responsible for generating feeds.
• Eager Loading Configuration: Configured SQLAlchemy's selectinload for Rom.files and joinedload with load_only for RomFile.rom to efficiently load associated RomFile data when Rom objects are queried, fetching only necessary Rom attributes (fs_path, fs_name).
• Code Simplification: Removed the now redundant get_rom_files method from RomsHandler as its functionality is superseded by the new eager loading strategy.

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[gemini-code-assist]

Code Review

This pull request effectively addresses a performance bottleneck in the feeds endpoint by tackling an N+1 query problem. The changes replace direct database calls within loops with pre-loaded SQLAlchemy relationships, which is a great optimization. The core of the fix is the intelligent use of selectinload with joinedload and load_only to efficiently fetch related RomFile data without causing further lazy loads or fetching redundant data. The removal of the now-unused get_rom_files method is also a good cleanup. Overall, these are solid improvements for performance and code maintainability.

[github-actions]

☂️ Python Coverage

current status: ✅

Overall Coverage

Lines	Covered	Coverage	Threshold	Status
11927	7679	64%	0%	🟢

New Files

No new covered files...

Modified Files

File	Coverage	Status
backend/endpoints/feeds.py	22%	🟢
backend/endpoints/rom.py	44%	🟢
backend/handler/database/roms_handler.py	52%	🟢
TOTAL	39%	🟢

updated for commit: 562d976 by action🐍

[github-actions]

Test Results

677 tests  ±0   676 ✅ ±0   1m 16s ⏱️ -1s
  1 suites ±0     1 💤 ±0 
  1 files   ±0     0 ❌ ±0 

Results for commit 562d976. ± Comparison against base commit c0abcd6.

[zurdi15]

Looks good to me, I don't think download will break