chore: bump lib-core.panel dep to 0.2.0

Track lib-core.panel v0.2.0 (multi-active panels with layout-slots).
No behavioral change in this consumer — the v0.1.1 call sites remain
compatible via the panel framework's bw-compat shim.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

manifest.lib

@@ -6,6 +6,6 @@
     "deps": [
         {"id": "lib-core.notify-display", "version": "0.1.0"},
         {"id": "lib-core.notify", "version": "0.1.0"},
-        {"id": "lib-core.panel", "version": "0.1.1"}
+        {"id": "lib-core.panel", "version": "0.2.0"}
     ]
 }