sweep ClideTappable across 15 files, remove 267 lines

23 StatefulWidget+State hover pairs converted to StatelessWidget
using ClideTappable(builder: (ctx, hovered, _) => ...). Covers
app.dart (5), welcome (2), claude session host (2), column hat (2),
spine (1), pane chrome (1), tab bar (1), decisions (1), tickets (1),
graph (1), pql panel (1), backlinks (1), file tree (2), git panel (1),
git status (1). Only EditorDragHandle and ClidePalette excluded
(drag/keyboard behavior beyond hover+tap).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

lib/builtin/pql/src/backlinks_view.dart

@@ -140,31 +140,22 @@ class _LinkGroup extends StatelessWidget {
   }
 }
 
-class _LinkRow extends StatefulWidget {
+class _LinkRow extends StatelessWidget {
   const _LinkRow({required this.link, required this.pathKey});
   final Map<String, Object?> link;
   final String pathKey;
 
-  @override
-  State<_LinkRow> createState() => _LinkRowState();
-}
-
-class _LinkRowState extends State<_LinkRow> {
-  bool _hover = false;
-
   @override
   Widget build(BuildContext context) {
     final tokens = ClideTheme.of(context).surface;
-    final target = widget.link[widget.pathKey] as String? ?? '';
-    final alias = widget.link['alias'] as String?;
+    final target = link[pathKey] as String? ?? '';
+    final alias = link['alias'] as String?;
     final display = alias ?? target;
 
-    return MouseRegion(
-      cursor: SystemMouseCursors.click,
-      onEnter: (_) => setState(() => _hover = true),
-      onExit: (_) => setState(() => _hover = false),
-      child: GestureDetector(
-        behavior: HitTestBehavior.opaque,
+    return Semantics(
+      button: true,
+      label: target,
+      child: ClideTappable(
         onTap: () {
           if (!target.startsWith('http')) {
             final kernel = ClideKernel.of(context);
@@ -172,21 +163,17 @@ class _LinkRowState extends State<_LinkRow> {
                 kernel.ipc.request('editor.open', args: {'path': target}));
           }
         },
-        child: Semantics(
-          button: true,
-          label: target,
-          child: Container(
-            color: _hover ? tokens.sidebarItemHover : null,
-            padding:
-                const EdgeInsets.symmetric(horizontal: 20, vertical: 2),
-            child: ClideText(
-              display,
-              maxLines: 1,
-              overflow: TextOverflow.ellipsis,
-              color: target.startsWith('http')
-                  ? tokens.statusInfo
-                  : tokens.sidebarForeground,
-            ),
+        builder: (context, hovered, _) => Container(
+          color: hovered ? tokens.sidebarItemHover : null,
+          padding:
+              const EdgeInsets.symmetric(horizontal: 20, vertical: 2),
+          child: ClideText(
+            display,
+            maxLines: 1,
+            overflow: TextOverflow.ellipsis,
+            color: target.startsWith('http')
+                ? tokens.statusInfo
+                : tokens.sidebarForeground,
           ),
         ),
       ),