feat: Add TUI retest shortcuts

[sakuyamaij]

Summary

• add r to rerun all proxy tests from the TUI list view
• add r in the detail panel to rerun only the selected proxy
• reset the progress bar immediately when a full rerun starts
• expose a single-proxy speed test entrypoint and cover the new TUI flows with tests

Testing

• go test ./...

Notes

• interactive -output runs now save the latest rerun state instead of only the initial run results
• fix existing log.Fatalln("... %s", err) vet issues in main.go while getting the full test suite green