SEP-1521: Extract a shared backup response base for the three backup apps - #1127

Pull request overview

This PR standardizes the “backup-family” task response surface across backup_mongo, backup_pg, and mysql_backups by extracting a shared response base and aligning response model naming, then regenerating OpenAPI snapshots and the frontend API client to match the updated schema.

Changes:

• Introduce a shared BackupTaskBase(BaseTaskResponse) carrying hostname and reuse it across the three backup apps.
• Rename mysql_backups BackupResponse → BackupTaskResponse and update route/dep/test references accordingly.
• Regenerate OpenAPI golden snapshots and the frontend OpenAPI spec + generated TypeScript client for the new component names.

Reviewed changes

Copilot reviewed 11 out of 12 changed files in this pull request and generated 2 comments.

@peter-o-addo — clean, tightly-scoped extraction. The shared BackupTaskBase kills the hostname triplication exactly as the ticket asks, living alongside framework so that layer stays domain-neutral; backup_type stays optional on the mysql child (confirmed in the regenerated snapshot — it's nullable and not in required); and the rename is complete, with no lingering BackupResponse references left in app/, tests/, or frontend/. test_exposes_inherited_task_response_surface still genuinely exercises the repointed inheritance.

One thing worth noting on scope: the AC said the backup_mongo / backup_pg snapshots would be unchanged, but both moved (PaginatedResponse_BackupTaskResponse___1→___2 and ___2→___3). That's correct and unavoidable — renaming mysql's class to BackupTaskResponse makes it a three-way name collision, so FastAPI mangles all three with module-qualified keys and renumbers the order-dependent suffixes. Regenerating those snapshots was the right call; the AC just under-counted the blast radius.

A few optional docstring nits, posted inline as one-click suggestions — all cases of a :type:/:rtype: line restating an annotation the signature already carries (backup_responses.py:33, mysql_backups/models.py:651, deps.py:168).

On the two open Copilot threads:

• backup_responses.py:26 — the suggested change (import from framework.responses) won't actually avoid the framework/__init__ side effects: Python runs a package's __init__ for any submodule import, so importing framework.responses still executes all of framework/__init__'s re-exports (I confirmed this directly). The real inaccuracy is the module docstring's claim that the layer is shared "without importing framework.__init__ and unrelated SQLModel tables into scope" — that's the part worth softening, not the import line.
• test_models.py:117 — agree; the "Tests for …" opener reads as a noun phrase, so an imperative verb (e.g. "Cover …") fits the convention.

Nothing blocking — all findings are cosmetic. Approving.

@peter-o-addo — all four points from the last round are addressed: BackupTaskBase now lives at app/sep/apps/shared/backups/responses.py alongside columns.py / edit_form.py, it is exported through shared/backups/__init__.py, the three consumers import it from the submodule (matching how BACKUP_TYPE_COLUMN and parse_server_list_config are already imported), and the three redundant :type: / :rtype: directives are gone. No new issues in the fix commits.

Minor — stale path in the PR Summary. The Summary still lists app/sep/apps/backup_responses.py : new shared BackupTaskBase(BaseTaskResponse); that module was removed by the move. Worth updating the bullet to the new path before merge so the description matches the diff.

LGTM.