feat(size): Ensure builds endpoint has parity with list-builds endpoint

[NicoHinderling]

in preparation for moving only remaining user of list-builds endpoint to the builds endpoint

artifact_search.py — Added state to the search config so the builds endpoint can filter
by artifact state via query string (e.g. state:3), replacing the dedicated state param
the old list-builds endpoint had.

builds.py — Three changes for parity with the list-builds endpoint it replaces:

1. Added select_related/prefetch_related to avoid N+1 queries during artifact
   transformation
2. Set default_per_page=25, max_per_page=100 to match list-builds pagination
3. Added per-artifact error handling in on_results so one bad artifact doesn't break
   the whole response

[NicoHinderling]

• feat(size): Kill list-builds endpoint in favor of builds endpoint #110272
• feat(size): Migrate size compare build selection page to builds endpoint #110271
• feat(size): Ensure builds endpoint has parity with list-builds endpoint #110270 👈 (View in Graphite)
• master

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[cursor]

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[chromy]

lgtm % 1 comment - thanks!