Parse flags/configs using urfave/cli/v3

[ChausseBenjamin]

Urfave cli is greate for parsing flags since it does many things in one which are closely related:

• argument validation (ensures a path is valid or a resolution matches an <int>p such as 720p)
• multiple sources for arguments: long/short flags (--downloads-path/-d), environment variables and toml config files (and other formats if desired)
• flag/config documentation
• flag/config priority (directly calling a flag like --downloads-path takes precedence over what's defined in gophertube.toml

I made a new GOPHERTUBE_CONFIG environment variable that lets users put their toml config wherever they want in case they don't like the default.

Also, it pre-packages the -v/--version and -h,--help flags for you so you don't have to update them as your flags/versions evolve.

What some flags now look like

$ gophertube --help
NAME:
   GopherTube - Terminal YouTube Search & Play

USAGE:
   GopherTube [global options]

VERSION:
   dev

DESCRIPTION:
   Gophertube is a terminal-based YouTube search and video player application.
   Navigate through YouTube content efficiently using keyboard shortcuts and enjoy
   seamless video playback directly from your terminal.

   Controls:
     • Type your search query and press Enter
     • Use ↑/↓ to navigate results
     • Press Tab to load more results
     • Press Esc to go back or exit


AUTHOR:
   KrishnaSSH <krishna.pytech@gmail.com>

GLOBAL OPTIONS:
   --config string, -c string          (default: $HOME/.config/gophertube/gophertube.toml) [$GOPHERTUBE_CONFIG]
   --downloads-path string, -d string  (default: $HOME/Videos/GopherTube)
   --search-limit int, -l int          (default: 30)
   --quality string, -q string         (default: "720p")
   --help, -h                          show help
   --version, -v                       print the version

$ gophertube -v
GopherTube version dev

You'd no longer have the ANSI colors with those flags, but the new general structure would be quite robust.

[KrishnaSSH]

Thanks for the PR! ❤️