Feature: tri-state banner size option

[cereda]

Here we go. 😉

I've implemented a tri-state option --banner-size to set the banner size:

Value	Result
None	No banner is displayed
Compact	A compact, one-line banner
Normal	ASCII art banner

(--banner-size compact should be equivalent to --compact-banner)

Speaking of which:

#[arg(long, group = "legacy", conflicts_with = "banner_size")]
compact_banner: bool,

I followed the deprecation route, so --compact-banner can be removed in two major releases (advise users to move to use --banner-size instead). Of couse, @avelino has the last word, so what he decides goes. 😉

To avoid an unnecessary level of complexity, --compact-banner (CLI) or compact_banner (configuration) has higher priority over --banner-size (CLI) or banner_size (configuration), so the removal of the deprecated option can be smooth.

Hope it flies! 🚀

[avelino]

The tri-state idea is good, but there are some issues that block merge:

Blocker: does not compile

• BannerSize::NORMAL does not exist — Rust enums are PascalCase, should be BannerSize::Normal
• Same issue in the TOML test: banner_size = "NORMAL" won't deserialize without #[serde(rename_all)]
• Need to align serde with clap. Suggestion: add #[serde(rename_all = "lowercase")] to the enum and use "normal", "compact", "none" in both CLI and TOML

Commented-out code

//compact_banner and //let compact_banner = config.compact_banner — remove these, commented-out code shouldn't go into main

Tests

• Missing test for BannerSize::None (stub without echo, no banner)
• Missing test for BannerSize::Compact
• Missing test for compact_banner vs banner_size priority in config

Deprecation warning

--compact-banner is marked as deprecated in the help text, but no warning is emitted when used. Without that, nobody will know they need to migrate. Suggestion:

if compact_banner {
    tracing::warn!("--compact-banner is deprecated, use --banner-size compact instead");
}

Minor

BannerSize::None can be confused with Option::None — consider Off or Hidden