improved docs about colors

[rawnly]

Hi there, I was struggling understanding the format for the configuration file and then the colors supported, so I thought that maybe it could be helpful to some other people. (I had visibility issues with my setup)

[Copilot]

Pull request overview

Updates documentation to make McFly’s color configuration easier to understand by adding an example TOML config and enumerating supported color names in the README.

Changes:

• Added docs/example-config.toml demonstrating [colors.*] configuration.
• Extended the README with a link to the example config and a “Supported Colors” list.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
docs/example-config.toml	Adds a sample TOML snippet showing how to set menu bar and dark mode colors.
README.md	Documents where to configure colors, links to the example file, and lists supported color names.

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[Copilot]

This paragraph says the config lives under $XDG_DATA_DIR/mcfly, but the implementation builds the path via directories_next::ProjectDirs::data_dir() (see Settings::mcfly_config_path in src/settings.rs), which corresponds to the XDG data home location (commonly $XDG_DATA_HOME / ~/.local/share/...), not an XDG_DATA_DIR env var. Please update the README to reference the correct env var/path so users can find config.toml reliably.

Suggested change

[Color settings](https://github.com/cantino/mcfly/blob/b54adb65e1567887fe430188324c09553431eb7c/src/settings.rs#L508) can be set in a config file, which will be in `~/.mcfly` if it exists, otherwise in `$XDG_DATA_DIR/mcfly`. On MacOS, this would be `~/Library/Application Support/McFly/config.toml`. You can find an example configuration [here](./docs/exmaple-config.toml)

[Color settings](https://github.com/cantino/mcfly/blob/b54adb65e1567887fe430188324c09553431eb7c/src/settings.rs#L508) can be set in a config file, which will be in `~/.mcfly` if it exists, otherwise in your XDG data home (commonly `$XDG_DATA_HOME/mcfly` or `~/.local/share/mcfly` on Linux). On MacOS, this would be `~/Library/Application Support/McFly/config.toml`. You can find an example configuration [here](./docs/exmaple-config.toml)