fix: fix Planner-Sisyphus visibility for OpenCode 1.1.1

- Change Planner-Sisyphus mode from "all" to "primary" for proper Tab selector visibility
- Fixes agent visibility breaking changes introduced in OpenCode 1.1.1
- 🤖 GENERATED WITH ASSISTANCE OF [OhMyOpenCode](https://github.com/code-yeongyu/oh-my-opencode)

src/plugin-handlers/config-handler.ts

@@ -178,7 +178,7 @@ export function createConfigHandler(deps: ConfigHandlerDeps) {
         const defaultModel = config.model as string | undefined;
         const plannerSisyphusBase = {
           model: (migratedPlanConfig as Record<string, unknown>).model ?? defaultModel,
-          mode: "all" as const,
+          mode: "primary" as const,
           prompt: PLAN_SYSTEM_PROMPT,
           permission: PLAN_PERMISSION,
           description: `${configAgent?.plan?.description ?? "Plan agent"} (OhMyOpenCode version)`,