Accept forceRefetch in plugin list requests (#34573)

## What changed

- Add the optional `forceRefetch` boolean to `PluginListParams` and generated schemas.
- Accept both omitted and enabled values without changing `plugin/list` behavior yet.
- Cover deserialization of the enabled value in the protocol tests.

GitOrigin-RevId: fd4145161e9779638bc0bf18118d5ab5b8478745

codex-rs/app-server-protocol/src/protocol/v2/plugin.rs

@@ -135,6 +135,9 @@ pub struct PluginListParams {
     /// the default remote catalog when enabled by feature flag.
     #[ts(optional = nullable)]
     pub marketplace_kinds: Option<Vec<PluginListMarketplaceKind>>,
+    /// Whether the client requests a fresh remote plugin catalog fetch.
+    #[serde(default, skip_serializing_if = "std::ops::Not::not")]
+    pub force_refetch: bool,
 }
 
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, JsonSchema, TS)]