feat!: Implements default keybindings for all actions.

This is a breaking change to the way the plugin is configured. If users are using the old configuration the plugin will warn them which fields have been removed in their configuration. Old keybindings can be found here: https://github.com/harrisoncramer/gitlab.nvim/pull/340#issuecomment-2282756924 (#331)

feat: Customize discussion tree chevrons (#339)

lua/gitlab/init.lua

@@ -34,7 +34,8 @@ return {
       args = {}
     end
     server.build() -- Builds the Go binary if it doesn't exist
-    state.merge_settings(args) -- Sets keymaps and other settings from setup function
+    state.merge_settings(args) -- Merges user settings with default settings
+    state.set_global_keymaps() -- Sets keymaps that are not bound to a specific buffer
     require("gitlab.colors") -- Sets colors
     reviewer.init()
     discussions.initialize_discussions() -- place signs / diagnostics for discussions in reviewer