Accumulate OpenCode settings restarts behind Apply & Restart

Defer OpenCode reloads after settings mutations, track pending changes,
and expose a top-right Apply & Restart OpenCode action with a counter so
sessions stay available until the user explicitly applies.

Co-authored-by: Serhii Dziupin <makeittech@users.noreply.github.com>

packages/ui/src/lib/api/types.ts

@@ -1356,6 +1356,11 @@ export interface SkillsInstallResponse {
   skipped?: Array<{ skillName: string; reason: string }>;
   error?: SkillsInstallError;
   requiresReload?: boolean;
+  requiresRestart?: boolean;
+  restartDeferred?: boolean;
+  requiresManualRestart?: boolean;
+  reloadFailed?: boolean;
+  warning?: string;
   message?: string;
   reloadDelayMs?: number;
 }