Allow direct subtitle delay entry

[Tavaresiqueira]

Summary

This makes the subtitle delay value in the player subtitles menu directly editable while keeping the existing +/- buttons at 0.25s increments.

The motivation is a real playback case where subtitles were more than 40 seconds out of sync. With only 0.25s steps, reaching the rough offset requires too many repeated clicks before fine tuning can even start.

Behavior

• Users can type the delay in seconds directly in the existing delay stepper.
• Enter or blur commits the typed value; Escape restores the current value.
• The +/- buttons still adjust by 0.25s for precise tuning after the rough offset is entered.
• Size and vertical position steppers remain display-only values with buttons, matching their previous behavior.
• The existing subtitleDelay stream state path is unchanged, so remembered subtitle timing continues to work as before.

Validation

• npx --yes pnpm@10.12.1 lint
• npx --yes pnpm@10.12.1 build

The production build still reports the existing webpack asset/entrypoint size warnings.

[CLAassistant]

All committers have signed the CLA.

[kKaskak]

you can hold the button to fast forward to the value you want tho?

[kKaskak]

The motivation is a real playback case where subtitles were more than 40 seconds out of sync. With only 0.25s steps, reaching the rough offset requires too many repeated clicks before fine tuning can even start.

this not true explained in the comment before

[joao-siqueira-genoa]

The motivation is a real playback case where subtitles were more than 40 seconds out of sync. With only 0.25s steps, reaching the rough offset requires too many repeated clicks before fine tuning can even start.

this not true explained in the comment before

You're right, the PR description is too strong there. Holding the button means the user does not need repeated individual clicks, so I should not phrase it as only 0.25s manual steps.

The gap I wanted to solve is narrower: when the user already knows the delay is very large, e.g. around 40s, direct entry is still faster and more precise than holding and trying not to overshoot. The existing hold-to-repeat and 0.25s +/- controls remain useful for fine tuning.

I can update the PR description to make that distinction clear, or close the PR if you think hold-to-repeat is enough for this UX.