[ refactor ] ditching contrib

[stefan-hoeck]

It is time to give pack some new attention and a bit of an overhaul. The Idris ecosystem has grown considerable, but pack still depends on contrib and a toml-parser library about which I'm not sure it is still being maintained. It also depends on the (slow) parser for .ipkg files and thus on the large idris2 API.

With this PR, I'm planning to ditch those dependencies, and use fast manual parsers for .toml and .ipkg files.

With this PR, I'm planning to ditch the dependencies on contrib and toml, and use fast manual parsers for .toml files. In a later step, I also plan to ditch the dependency on the Idris API.

• [x] use parser-toml for parsing .toml files
• [x] use idris2-getopts for parsing command-line options
• [x] drop dependencies on contrip and toml

[stefan-hoeck]

It is expected that installing from the bash script fails here, because this clones the main branch and with the current main, the dependencies don't match. Therefore, I'm going to merge this later today.