Paginate partitioned Dag run modal requests

[steveahnahn]

Adds server-side pagination to the private UI endpoint behind the pending partitioned Dag run modal, and wires the modal table state to limit and offset.

Why:

• The endpoint materialized every matching AssetPartitionDagRun row before enrichment.
• The response total was derived from the materialized row list, so the UI had no way to page through the full filtered result set.
• The modal did not pass pagination state to the generated client, so opening it for a large partitioned Dag could request and render every pending partition.

What changed:

• Accept standard limit and offset query parameters on /ui/partitioned_dag_runs.
• Use paginated_select so the endpoint returns the full filtered total while enriching only the current page of rows.
• Preserve the missing-Dag 404 behavior and return an empty page with the real total when offset is past the end.
• Keep modal pagination local to the dialog, pass limit and offset to the generated client, and reset the dialog page index on close.
• Regenerate the private UI OpenAPI client and add backend/UI regression coverage.

Validation:

• Reproduction before fix: applying only the backend regression test to upstream/main failed because limit=2 still returned ["key-2", "key-1", "key-0"].
• Added backend regression coverage for first page, second page, and empty page past the end: TestGetPartitionedDagRuns.test_should_paginate_partitioned_dag_runs.
• Added UI coverage in PartitionScheduleModal.test.tsx for initial page, next page, and close/reset query parameter wiring.
• Breeze UI smoke with 105 pending partitioned Dag runs confirmed the modal requested limit=50&offset=0, then limit=50&offset=50, then limit=50&offset=100; the final response contained 5 rows with total=105.

Screenshots

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Was generative AI tooling used to co-author this PR?

• Yes - Codex (GPT-5)

Generated-by: Codex (GPT-5) following the guidelines

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Note

✅ Ready for review · @steveahnahn → @potiuk · 2026-06-12 13:30 UTC

Thanks @steveahnahn — all checks are green and this PR is marked ready for maintainer review. The ball is with the maintainers now; a maintainer will take the next look.

_{Automated triage — may be imperfect.}