feat: interactive mode learns 'toggle [a]ll' and 'remove [a]ll'.

In the mark pane, the 'a' key will now toggle all entries.
This is particularly interesting for selecting entries to
exclude by hande and then invert the selection by toggling [a]ll.

In the mark pane, toggling all with the 'a' key means removing
all entries and closing the pane.

src/interactive/widgets/entries.rs

@@ -182,7 +182,7 @@ impl Entries {
                 );
             }
             let bound = line_bound(bound, bound.height.saturating_sub(1) as usize);
-            let help_text = " mark-move = d | mark-toggle = space ";
+            let help_text = " mark-move = d | mark-toggle = space | toggle-all = a";
             let help_text_block_width = block_width(help_text);
             if help_text_block_width <= bound.width {
                 draw_text_nowrap_fn(

src/interactive/widgets/mark.rs

@@ -412,7 +412,7 @@ impl MarkPane {
                 );
             }
             let bound = line_bound(bound, bound.height.saturating_sub(1) as usize);
-            let help_text = " mark-toggle = space|d";
+            let help_text = " mark-toggle = space,d | remove-all = a";
             let help_text_block_width = block_width(help_text);
             if help_text_block_width <= bound.width {
                 draw_text_nowrap_fn(