savefig_paper caption-visibility restore is not exception-safe under EPS_PLOT_NO_CAPTION=1

target_file: src/explore_persona_space/analysis/paper_plots.py problem: savefig_paper's caption-hiding path is not exception-safe. Under EPS_PLOT_NO_CAPTION=1 the function temporarily hides caption artists before saving and restores their visibility afterward, but the restore is not guarded by try/finally. If the save itself raises — a bad path, a permissions error, an out-of-space condition, a backend failure — the function unwinds with the caption artists left INVISIBLE on the still-live Figure object. Any subsequent save of that same figure (a retry, a second format, a caller that catches and re-saves) then silently produces a caption-less figure, with no error and nothing in the sidecar to indicate the caption was dropped. fix_sketch: wrap the hide/restore span in try/finally so visibility is restored on every exit path, including exceptions. Add a regression test that monkeypatches the save call to raise while EPS_PLOT_NO_CAPTION=1 is set, then asserts every caption artist's get_visible() is back to its pre-call value. Check whether the same non-exception-safe pattern appears in any sibling temporary-mutation span in the same function (presentation-env overrides, per-format provenance embed) — if so, cover them in the same pass. confidence: high

Provenance

Surfaced by the Codex twin (epm:code-review-codex v3) during the round-3 code review of task #2262, as machine-readable concern savefig-caption-restore-not-exception-safe. Codex itself routed it as "address separately with finally cleanup".

It is PRE-EXISTING and entirely unrelated to #2262's diff: #2262's final round changed exactly one line — a # noqa: C901 comment on savefig_paper's def line — and its substantive rounds touched only _extract_scatters / _has_explicit_offsets. Nothing in #2262 caused or worsened this defect.

Filed as its own task rather than absorbed into #2262 because #2262's Goal is the _extract_scatters sidecar-capture bug; a caption-visibility restore bug would change that Goal. The concern remains recorded in #2262's ledger with a pointer here.

This is library code under src/explore_persona_space/analysis/, NOT workflow surface, so the workflow-fix-on-bug auto-file-and-spawn protocol does not route it — hence a plain proposed capture with no session spawned. Dispatch is the user's / PM's call.

Why it is worth fixing

savefig_paper is the project's single figure-save entry point, so a silent caption drop is a correctness risk for any reader-facing artifact rendered through a retry path. The failure mode is silent by construction: the sidecar records no marker for a dropped caption, so a caption-less figure is indistinguishable from an intentionally caption-free one after the fact.