ci(tauri-release): always dump + upload smoke-test app logs

[shiba4life]

Summary

The Tauri `dmg-smoke` step launches the bundled app and probes `/api/health`, but only prints `$RUNNER_TEMP/app.log` on failure. Successful runs discarded the app's startup output entirely, which made debugging anything (flaky behavior, slow startup, deprecation warnings) require a failure to have already happened.

This PR makes the smoke logs always visible:

1. Replace the `if: failure()` dump with `if: always()`.
2. Print both log sources, not just one:
   • `$RUNNER_TEMP/app.log` — process stdout/stderr (panics, early prints before the tracing subscriber composes)
   • `~/Library/Logs/com.folddb.app/FoldDB.log` — tauri-plugin-log output, populated by the pre-Builder file logger added in fix(tauri): pre-Builder file logger captures every startup line #777
3. Upload both as a `dmg-smoke-app-logs` artifact (14-day retention) so they're downloadable for offline triage.

Why both logs

The two streams capture different startup phases. stdout has panics + the few seconds before the tracing subscriber is wired; the file logger has structured `tracing::*` output once `init_pre_builder_file_logger()` runs. Triaging a startup failure usually needs the union — printing only stdout was leaving the structured-trace half on the floor.

Test plan

• YAML syntax checked locally (file edits compile-cleanly with the existing structure)
• CI green on this PR
• Next `workflow_dispatch` of `tauri-release.yml` shows both log sections in the dmg-smoke step output

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