sessions: failsafe session is now accessible via separate launcher icon

[xeffyr]

Enables additional launcher icon that causes to be a failsafe session to be started instead of default.
This PR also makes session auto-closeable on exit coded 0 and 130. Any other exit codes should be handled by user on it's own in order to avoid messages about "Press enter".

Old "failsafe" session button left untouched since it may be useful in some cases to start system shell instead of Termux's one.

[xeffyr]

@fornwall I also made auto-closing for only "0" and "130" exit codes as we discussed on Gitter.

[eladts]

I don't like the solution of another launcher icon, it just creates clutter IMHO. Is there a reason why this functionality cannot be achieved using app shortcuts? Is there a way (without rooting) to remove the extra icon from the launcher?

[xeffyr]

Is there a reason why this functionality cannot be achieved using app shortcuts?

Not all launchers support shortcuts. Especially on older Android versions.

Is there a way (without rooting) to remove the extra icon from the launcher?

Check launcher settings if it allows to hide icon.

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Generally, this solution is final and should be fine for average user, i.e. should work on all ROMs and launchers.
Other variants that make environment recovery really hard will not be implemented.

[xeffyr]

btw, there always will be tradeoff for issues regarding "[Process completed - press Enter]" which will not be accepted by some users.

Decide what you want:

• Ability to retrieve files from $HOME in case of environment failure while having auto-closeable sessions.

• Or have to completely reinstall application with erasing all files (which may not be backed up) in $HOME due to denial-of-service condition because of shell failure ?

[eladts]

Thanks @xeffyr for the quick response! Unfortunately my launcher (stock launcher on Moto X4) does not support app hiding and I don't want to switch launchers for this reason alone. I would appreciate if there is an option to hide the extra launcher icon from within Termux, which as far as I understand the only way this can be done without rooting or switching to another launcher.