gpui: Store action documentation (#33809)

Closes #ISSUE

Adds a new `documentation` method to actions, that is extracted from doc
comments when using the `actions!` or derive macros.

Additionally, this PR adds doc comments to as many action definitions in
Zed as possible.

Release Notes:

- N/A *or* Added/Fixed/Improved ...

crates/zed/src/main.rs

@@ -1368,6 +1368,7 @@ fn dump_all_gpui_actions() {
         name: &'static str,
         human_name: String,
         aliases: &'static [&'static str],
+        documentation: Option<&'static str>,
     }
     let mut actions = gpui::generate_list_of_all_registered_actions()
         .into_iter()
@@ -1375,6 +1376,7 @@ fn dump_all_gpui_actions() {
             name: action.name,
             human_name: command_palette::humanize_action_name(action.name),
             aliases: action.deprecated_aliases,
+            documentation: action.documentation,
         })
         .collect::<Vec<ActionDef>>();
 

crates/zed/src/zed.rs

@@ -78,19 +78,33 @@ use zed_actions::{
 actions!(
     zed,
     [
+        /// Opens the element inspector for debugging UI.
         DebugElements,
+        /// Hides the application window.
         Hide,
+        /// Hides all other application windows.
         HideOthers,
+        /// Minimizes the current window.
         Minimize,
+        /// Opens the default settings file.
         OpenDefaultSettings,
+        /// Opens project-specific settings.
         OpenProjectSettings,
+        /// Opens the project tasks configuration.
         OpenProjectTasks,
+        /// Opens the tasks panel.
         OpenTasks,
+        /// Opens debug tasks configuration.
         OpenDebugTasks,
+        /// Resets the application database.
         ResetDatabase,
+        /// Shows all hidden windows.
         ShowAll,
+        /// Toggles fullscreen mode.
         ToggleFullScreen,
+        /// Zooms the window.
         Zoom,
+        /// Triggers a test panic for debugging.
         TestPanic,
     ]
 );