fix: add click_handler attr for GridAction

sometimes caller just needs to do something unique, so let them

src/wuttaweb/grids/base.py

@@ -2284,6 +2284,16 @@ class GridAction:
 
        Optional ``target`` attribute for the ``<a>`` tag.
 
+    .. attribute:: click_handler
+
+       Optional JS click handler for the action.  This value will be
+       rendered as-is within the final grid template, hence the JS
+       string must be callable code.  Note that ``props.row`` will be
+       available in the calling context, so a couple of examples:
+
+       * ``deleteThisThing(props.row)``
+       * ``$emit('do-something', props.row)``
+
     .. attribute:: icon
 
        Name of icon to be shown for the action link.
@@ -2302,6 +2312,7 @@ class GridAction:
             label=None,
             url=None,
             target=None,
+            click_handler=None,
             icon=None,
             link_class=None,
     ):
@@ -2311,6 +2322,7 @@ class GridAction:
         self.key = key
         self.url = url
         self.target = target
+        self.click_handler = click_handler
         self.label = label or self.app.make_title(key)
         self.icon = icon or key
         self.link_class = link_class or ''

src/wuttaweb/templates/grids/vue_template.mako

@@ -183,6 +183,9 @@
                    % if action.target:
                        target="${action.target}"
                    % endif
+                   % if action.click_handler:
+                       @click.prevent="${action.click_handler}"
+                   % endif
                    class="${action.link_class}">
                   ${action.render_icon_and_label()}
                 </a>