Add aliases for key bindings

[ek4]

Feature description

Add aliases for key bindings, for example F5 on meta2-15~ and meta2-[E, so that the key F5 can be used directly in a key binding: /key bind F5 /some_command.

[weechatter]

All the weird codes are the peculiarity of terminal key handling. There is no magic mapping of all
the keys things, because WeeChat just uses whatever the terminal tells it.
Therefore you have the alt+k mode, see /help key

[arza-zara]

I think this is a viable suggestion, not invalid. For example we could have aliases like F1 -> meta2-11~ & meta-OP.

[flashcode]

Hi @ek4,

I'm writing a specification that addresses this issue (but not only): https://specs.weechat.org/specs/2023-002-key-bindings-improvements.html

This is still a draft and not complete, but your feedback is welcome on the proposed changes.

Note: to be consistent, all new key names (aliases) are lower case, that means meta2-15~ (and meta2-[E) become f5 (lower case) and alt+k will return f5.

[flashcode]

Hi,

For your information I pushed the branch key-bindings-improvements (work in progress):

• add of /debug key that displays the new key name using alias (eg: meta2-1;3D is now meta-left)
• configuration is unchanged for now: it is fully compatible with master branch, keys are not yet renamed in config.

Please try with many terminals and different keys to ensure all keys are properly converted to the new name.
If not, please ping me.

[flashcode]

All changes are implemented on the branch.

As there are many breaking changes, please send feedback before it's merged and available for all testers of development version.