feat: add column picker to log viewer

[wolffberg]

This PR adds a custom column picker for the log viewer.

The picker is opened with C when the log viewer is active and lets you pick custom columns from a discovered list from the incoming logs.

[destari]

Hey @wolffberg ! I'm trying this out, and noticed Space to toggle a column does not work (but 'x' does)

Still reviewing

[destari]

I like the idea of configurable columns, but the changes included here are vast, and cause a lot of column sizing breakage, log line issues, etc., and some of the help around using arrow keys is either wrong or it just does not work.

Perhaps reduce the changes to only allow choosing columns, and be sure to test on wide screens and dynamic changing window sizes, etc.

[destari]

Needs a lot of work on the column sizing, truncation of log messages in the main window, help adjustments, etc. Reduce changes to the minimum

[wolffberg]

Regarding space I was sure it was a local issue with my TMUX settings (hence why I added x).

I agree that the changes might be a bit too broard. I'll redo the changes to reduce the scope a little.

Converting to draft and will get back later this week or next week with changes 👷

I have a few questions for changes though.

1. If columns have spaces in them, it can be hard tosee where one column ends and the other begins. Do you think the spaces should be replaced, a column divider should be added, quotes added to the header or something else?
2. In k8s-mode, all columns turn into Kubernetes metadata like labels. Should this be the case or should it pick columns from the log line like in normal mode?