Add way to provide extra initCommands

[gollth]

Hello,

first of all thanks for this great plugin, it's my daily driver for a long time one 🙏

I have a particular feature that I'm lacking or don't know how to achieve in rustaceanvim when it comes to debugging: I have a custom lldb init script in my repo (which adds some custom formatters) which I want to apply to every debuggable target there is (executables, nvim-dap targets & neotest debug targets), when using the codelldb adapter.

AFAIK I can only provide initCommands in the .vscode/launch.json, which works for executables, but not for the tests, right?

My idea was let the user configure an optional command in its config, which gets appended to all other init commands of all targets. My user config now looks like this:

  {
    "mrcjkb/rustaceanvim",
    dependencies = { "mfussenegger/nvim-dap" },
    version = "^5",
    lazy = false,
    ft = { "rust" },
    opts = {
      dap = {
        autoload_configurations = true,
        init_commands = "command script import ./lldb/fleet.py",
      },
    }
    -- other config...
}

Maybe there is another already built in way how to solve this, comments very welcome (=

[github-actions]

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[mrcjkb]

Hey 👋

Thanks for the PR.
Is something like this supported by the rust-analyzer VSCode plugin or by rust-analyzer?
If not, I'd prefer it be requested there first.

Adding it to the rustaceanvim config feels quite hacky. I'd potentially be open to a more general solution, in which rustaceanvim doesn't have to be concerned with which extra fields are added to the DAP configurations.