feat: add support for toml configuration files + recursive flag definitions for subcommands

[anarcher]

Description

ffcli can take arguments to a config file and process them as follows (available with arguments)
IMHO, I think this is useful if you have a lot of arguments, like the gnokey cli. Unlike ENV, it is explicit e.g.-config=maketx.local

gnokey maketx call -config ./maketx.local.toml  -pkgpath "gno.land/r/demo/boards" -func "GetBoardIDFromName" -args test anarcher

maketx.local.toml

gas-fee = "1000000ugnot"
gas-wanted = 2000000
broadcast = true
chainid = "dev"
remote = "127.0.0.1:26657"

Contributors Checklist

• Added new tests, or not needed, or not feasible
• Provided an example (e.g. screenshot) to aid review or the PR is self-explanatory
• Updated the official documentation or not needed
• No breaking changes were made, or a BREAKING CHANGE: xxx message was included in the description
• Added references to related issues and PRs
• Provided any useful hints for running manual tests

Maintainers Checklist

• Checked that the author followed the guidelines in CONTRIBUTING.md
• Checked the conventional-commit (especially PR title and verb, presence of BREAKING CHANGE: in the body)
• Ensured that this PR is not a significant change or confirmed that the review/consideration process was appropriate for the change

[jaekwon]

I'm not as familiar with ffcli, so I'll leave to others to consider the ramifications.

[moul]

Related with #762
Addresses #731