fix(opencode): disable session navigation commands when no parent session (#15762)

Co-authored-by: Test User <test@test.com>
Co-authored-by: Shoubhit Dash <shoubhit2005@gmail.com>

packages/opencode/src/cli/cmd/tui/routes/session/index.tsx

@@ -925,6 +925,7 @@ export function Session() {
       keybind: "session_parent",
       category: "Session",
       hidden: true,
+      enabled: !!session()?.parentID,
       onSelect: childSessionHandler((dialog) => {
         const parentID = session()?.parentID
         if (parentID) {
@@ -942,6 +943,7 @@ export function Session() {
       keybind: "session_child_cycle",
       category: "Session",
       hidden: true,
+      enabled: !!session()?.parentID,
       onSelect: childSessionHandler((dialog) => {
         moveChild(1)
         dialog.clear()
@@ -953,6 +955,7 @@ export function Session() {
       keybind: "session_child_cycle_reverse",
       category: "Session",
       hidden: true,
+      enabled: !!session()?.parentID,
       onSelect: childSessionHandler((dialog) => {
         moveChild(-1)
         dialog.clear()