Add complete keyboard navigation.

specs/editor_misc.allium

@@ -342,6 +342,8 @@ surface MetadataDiffSurface {
     @guarantee ScanAction
         -- Scan/Rescan button at top.
         -- Progress bar + message during scan.
+        -- Control+Option+R (macOS) or Control+Alt+R runs the scan; repair buttons use Tab
+        -- and are activated with Enter or Space.
 
     @guarantee EntityTabs
         -- Tabs: Posts, Media, Scripts, Templates — each with badge count of diffs.
@@ -443,6 +445,8 @@ surface SiteValidationSurface {
 
     @guarantee ApplyAction
         -- Apply button disabled when nothing to fix.
+        -- Control+Option (macOS) or Control+Alt, followed by R, scans and A applies;
+        -- both remain in Tab order.
         -- On apply: renders missing, deletes extra, re-renders updated.
         -- Toast: "Validation applied: N rendered, N deleted".
 }