[codex] Cache remote plugin catalog for suggestions (#25457)

## Summary
- cache the global remote plugin catalog when remote plugin listing runs
and warm it during startup
- use the cached remote catalog in plugin install recommendations with
canonical `plugin@openai-curated-remote` ids
- reuse the session `PluginsManager` for plugin recommendations so
remote cache state is visible on the recommend path
- skip core installed-state verification for remote plugin install
suggestions while leaving local plugin and connector verification
unchanged

## Testing
- `just fmt`
- `git diff --check`
- `cargo test -p codex-core
list_tool_suggest_discoverable_plugins_includes_cached_remote_global_plugins`
- `cargo test -p codex-core
remote_plugin_install_suggestions_skip_core_installed_verification`
- `cargo test -p codex-app-server
plugin_list_includes_remote_marketplaces_when_remote_plugin_enabled`

Earlier focused checks during the same branch: codex-tools TUI filter
test, request_plugin_install tests, and codex-app-server build.

codex-rs/app-server/src/request_processors/plugins.rs

@@ -662,6 +662,7 @@ impl PluginRequestProcessor {
                 &remote_plugin_service_config,
                 auth.as_ref(),
                 &remote_sources,
+                /*global_catalog_cache_path*/ Some(config.codex_home.as_path()),
             )
             .await
             {