Editable job names

[krokicki]

Adds human-editable names to jobs. Stacked on top of apps-improvements — review/merge that PR first.

What changed

At launch, a "Job name" field is prefilled with app name - entry point (editable before submit). The name becomes the job's identity throughout the UI, replacing the now-redundant App and Entry Point columns in the jobs table. It can be renamed afterward from the actions menu (dialog) or inline on the job detail page (GitHub-issue-title style: pencil → text field with Save/Cancel; Enter saves, Escape cancels).

Backend

• New nullable name column on jobs, backfilled for existing rows via migration (e7b2a9c4f130) with app_name - entry_point_name
• name added to the Job / JobSubmitRequest models and persisted at submit (defaults to app - entry when blank)
• New PATCH /api/jobs/{job_id} rename endpoint (400 on empty, 404 if not owned)
• _convert_job projects the app - entry fallback so the required Job.name is never null even for legacy rows

Frontend

• useUpdateJobMutation, the prefilled launch-form field, the jobs-table Name link column (App/Entry Point columns dropped), a rename dialog, and an inline editor on the detail page
• AppPageHeader.title now accepts a ReactNode (string callers unchanged) to host the inline editor

Testing

• Backend: full suite passes (735); new tests cover name defaulting/backfill, the rename endpoint (happy/empty/not-owner), and the migration
• Frontend: node-check clean (no new errors), production build succeeds
• Not yet run: interactive browser pass (launch prefill, table rename, inline save/Escape/empty-disable) — recommend a quick pixi run dev-launch check before merge

Spec: docs/superpowers/specs/2026-07-18-editable-job-names-design.md
Plan: docs/superpowers/plans/2026-07-19-editable-job-names.md

@StephanPreibisch @JaneliaSciComp/fileglancer