Fix nvim-treesitter lazy.nvim config by removing invalid 'main' field

[r0landd]

Problem

On Windows, setting main = 'nvim-treesitter.configs' causes lazy.nvim to attempt
require('nvim-treesitter.configs'), but this module does not exist in
nvim-treesitter. As a result, Neovim fails to load the plugin.

Other platforms may not trigger the same error, but the configuration
is invalid and can cause issues.

Solution

Remove the main field and rely on lazy.nvim’s default behavior, which
correctly calls require('nvim-treesitter.configs').setup(opts).

Result

Neovim starts normally on Windows (and other platforms) and treesitter
is configured as expected.

[r0landd]

Removing main avoids the error, but the config still needs a proper setup() call. I’ll reopen with a corrected config.