chore: add sproutclaw git workflow and track local extensions

Document main/upstream-sync/feature branch strategy, add sync/push
scripts, track .pi/agent extensions and webui in git, and disable
startup changelog via showChangelogOnStartup.

Co-authored-by: Cursor <cursoragent@cursor.com>

.pi/agent/extensions/webui/frontend/src/components/layout/AppLayout.module.css

@@ -0,0 +1,32 @@
+.app {
+  display: flex;
+  height: var(--app-height);
+  min-height: 0;
+}
+
+.main {
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  min-width: 0;
+  min-height: 0;
+  background: #fff;
+}
+
+.overlay {
+  display: none;
+  position: fixed;
+  inset: 0;
+  background: rgba(0, 0, 0, 0.3);
+  z-index: 99;
+}
+
+.overlayOpen {
+  display: block;
+}
+
+@media (max-width: 768px) {
+  .app {
+    height: var(--app-height);
+  }
+}