Add a new `keymaps` option to the lz-n plugin that allows users to define
keymaps that use lz.n's keymap(<plugin>).set functionality. This enables
users to create keymaps that lazy-load plugins when specific keys are pressed,
using the familiar vim.keymap.set() API style.
The implementation:
- Adds a new `keymaps` option using mkMapOptionSubmodule with a custom plugin property
- Exposes a simple and consistent interface for configuring lazy-loaded keymaps
- Processes these keymaps to generate corresponding Lua code with require('lz.n').keymap().set()
- Cleanly separates plugin specs from keymap definitions while preserving their relationship
This commit adds a `plugins.<name>.luaConfig` section controlling the
plugin specific configuration.
The section contains the internal `init` option, containing the plugin's
initialization code.
It also contains the public `pre` and `post` options, that allow to add
code before & after the `init` section
Finally, it contains the `final` option, being the concatenation of the
three previous options.
