Remove remaining `@kestra-io/ui-libs` references

[MilosPaunovic]

ui-libs is sunsetting - all components have been moved to ui/packages in the OSS repo. The following references need to be migrated or removed:

• astro.config.mjs
• package.json
• package-lock.json
• src/loaders/plugins.ts
• src/composables/usePluginsCount.ts
• src/components/MDCParserAndRenderer.vue
• src/components/MDCParserAndRenderer.astro
• src/components/layout.astro
• src/components/blueprints/Topology.client.vue
• src/components/careers/Positions.vue
• src/components/common/PluginsBlock.astro
• src/components/common/PluginsBox.astro
• src/components/common/SocialsList.vue
• src/components/docs/NavToc.vue
• src/components/layout/FeaturePlugins.astro
• src/components/plugins/OneHeader.astro
• src/components/plugins/PluginCard.vue
• src/components/plugins/PluginElements.vue
• src/components/plugins/PluginsMDCRender.vue
• src/components/plugins/PluginsIndexWrapper.vue
• src/components/plugins/SubgroupView.astro
• src/components/plugins/sidebar/PluginSidebar.vue
• src/components/plugins/sidebar/RightSideBar.vue
• src/components/plugins/similar-plugins/SimilarPlugins.astro
• src/components/plugins/versions/OverviewPanel.vue
• src/components/plugins/versions/Versions.vue
• src/components/price/PlanTable.astro
• src/pages/features/code-in-any-language/index.astro
• src/pages/features/code-in-any-language/julia.astro
• src/pages/features/code-in-any-language/python.astro
• src/pages/features/code-in-any-language/r.astro
• src/pages/meta/plugins/[...slug].svg.ts
• src/pages/meta/plugins/group-[cls].svg.ts
• src/pages/meta/plugins/plugin-[name].svg.ts
• src/pages/overview.astro
• src/pages/plugins/[...slug].astro
• src/pages/plugins/index.astro
• src/pages/sitemap/plugins.xml.ts
• src/utils/plugins/aliasMapping.ts
• src/utils/plugins/all.ts
• src/utils/plugins/buildPluginPageProps.ts
• src/utils/plugins/fetchPluginPageData.ts
• src/utils/plugins/generateNavigation.ts
• src/utils/plugins/generateSidebarPluginData.ts
• src/utils/plugins/nuxtBlocks.ts
• src/utils/plugins/pluginCount.ts
• src/utils/plugins/pluginUtils.ts
• src/utils/plugins/pruneForClient.ts
• src/utils/plugins/subgroupMatcher.ts
• src/utils/plugins/types.ts