fix(table): fix label display when a command + filter + label is provided

[tyzbit]

currently, if you use :svc -l app.kubernetes.io/instance=cert-manager in k9s and then navigate history, when returning to the page the results are correct but the filter is not shown. here, we ensure that the table title string is not an empty string.

reported in #3404, but unrelated

bug originally introduced in #3293, which I have not reviewed for any other rippling effects.

[uozalp]

@derailed This bug is still present in v0.50.7 with the refactored code.

[derailed]

@uozalp Thanks for the heads up! Just tried it on v0.50.9 and the behavior seems correct??
Could you double check me on this? perhaps I am missing it...

[uozalp]

@derailed I tested this again on v0.50.9, and the behavior is the same. When switching away from :pods and coming back, the label filter isn't preserved. That's expected though, since K9s doesn't currently support keeping filters across views.

Just to clarify, the issue I mentioned earlier #3404 (comment) was something I noticed while testing the PR from tyzbit:preserve-command-filter

I cherry-picked commit [421a0ea8b01a3cfaf3a1a5d54232a00e9ec8095b] onto v0.50.9 to try it out. There wasn't any visible change in the UI, which makes sense since the filter persistence feature hasn’t been implemented yet.

The code itself looks good and seems safe to merge, but on its own it probably doesn't add much value without the full preserve filter feature in place.

As already mentioned, that PR will need some rework after the navigation history refactor in v0.50.7. Still, it's a feature I'm really looking forward to. Having filters stick when navigating would be super useful