Improve list-actions command documentation formatting

This commit fixes two issues with the `list-actions` command:

1. Ensures all actions are listed, including those without individual
   documentation but sharing docs with related actions
2. Improves documentation formatting with proper indentation and grouping

src/cli/list_actions.zig

@@ -3,6 +3,7 @@ const args = @import("args.zig");
 const Action = @import("action.zig").Action;
 const Allocator = std.mem.Allocator;
 const help_strings = @import("help_strings");
+const KeybindAction = @import("../input/Binding.zig").Action;
 
 pub const Options = struct {
     /// If `true`, print out documentation about the action associated with the
@@ -36,18 +37,45 @@ pub fn run(alloc: Allocator) !u8 {
     }
 
     const stdout = std.io.getStdOut().writer();
-    const info = @typeInfo(help_strings.KeybindAction);
-    inline for (info.Struct.decls) |field| {
-        try stdout.print("{s}", .{field.name});
-        if (opts.docs) {
-            try stdout.print(":\n", .{});
-            var iter = std.mem.splitScalar(u8, std.mem.trimRight(u8, @field(help_strings.KeybindAction, field.name), &std.ascii.whitespace), '\n');
-            while (iter.next()) |line| {
-                try stdout.print("  {s}\n", .{line});
-            }
-        } else {
-            try stdout.print("\n", .{});
+
+    var buffer = std.ArrayList(u8).init(std.heap.page_allocator);
+    defer buffer.deinit();
+
+    const fields = @typeInfo(KeybindAction).Union.fields;
+    inline for (fields) |field| {
+        if (field.name[0] == '_') continue;
+
+        // Write previously stored doc comment below all related actions
+        if (@hasDecl(help_strings.KeybindAction, field.name)) {
+            try stdout.writeAll(buffer.items);
+            try stdout.writeAll("\n");
+
+            buffer.clearRetainingCapacity();
         }
+
+        // Write the field name.
+        try stdout.writeAll(field.name);
+        try stdout.writeAll(":\n");
+
+        if (@hasDecl(help_strings.KeybindAction, field.name)) {
+            var iter = std.mem.splitScalar(
+                u8,
+                @field(help_strings.KeybindAction, field.name),
+                '\n',
+            );
+            while (iter.next()) |s| {
+                // If it is the last line and empty, then skip it.
+                if (iter.peek() == null and s.len == 0) continue;
+                try buffer.appendSlice("  ");
+                try buffer.appendSlice(s);
+                try buffer.appendSlice("\n");
+            }
+        }
+    }
+
+    // Write any remaining buffered documentation
+    if (buffer.items.len > 0) {
+        try stdout.writeAll(buffer.items);
     }
 
     return 0;