(core) Expanding widgets

Summary:
New icon to expand an active section and show it as a popup (just like raw data views).

"Show raw data" popup couldn't be reused (as it is basically a different page), so now
we have two kinds of popups that look the same.

1. Raw data popup - to show an alien section on a page (a section from a different view). This is used by "Show raw data" button, it is basically a different page that shows an arbitrary section.

2. Layout popup - a popup generated by Layout.ts that basically hides every other section and adds an overlay effect to itself.

Other changes
- Layout.js was migrated to typescript
- "Show raw data" menu item was converted to link

Test Plan: new tests

Reviewers: georgegevoian

Reviewed By: georgegevoian

Differential Revision: https://phab.getgrist.com/D3764

app/client/components/ViewLayout.css

@@ -5,6 +5,11 @@
 
 .viewsection_buttons {
   margin-left: 4px;
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  align-self: flex-start;
+  margin-top: -1px;
 }
 
 .viewsection_title {
@@ -99,6 +104,19 @@
   border-left: 1px solid var(--grist-theme-widget-border, var(--grist-color-dark-grey));
 }
 
+/* Used by full screen section. Removes the green box-shadow and restores normal color of the border.
+   It still leaves the indicator for the cardlist selection (the green box shadow in card) which looks nice.
+*/
+.layout_box_maximized .active_section > .view_data_pane_container{
+  box-shadow: none;
+  border: 1px solid var(--grist-theme-widget-border, var(--grist-color-dark-grey));
+}
+/* Remove the drag indicator */
+.layout_box_maximized .active_section .viewsection_drag_indicator {
+  visibility: hidden !important;
+}
+
+
 .disable_viewpane {
   justify-content: center;
   text-align: center;