feat(skills): curated GitHub catalog redesign (#3016)

* feat(skills): remove ClawHub catalog integration

Drop the ClawHub registry as a skills catalog source across web server,
shared UI, VS Code, docs, and locales. The catalog now serves git-based
sources only: the curated Anthropic repo and user-defined repositories.
Also removes the now-unused adm-zip dependency.

* feat(skills): redesign catalog around curated GitHub repositories

Replace the single-source dropdown with a card grid of curated GitHub
repositories (Anthropic, OpenAI, Cursor pstack/skills, Matt Pocock) plus
user-defined sources. Source cards show skill counts, GitHub stars, and
last-updated time; a global search covers all loaded sources.

Server: curated sources gain GitHub repo metadata (stars, pushed_at)
fetched best-effort with a 3-hour in-memory and on-disk cache; scans
run through a concurrency-limited, deduplicated cache with 3-hour TTL
persisted across restarts. Refresh still bypasses the cache.

Shared UI: source cards, global search with clear button, per-skill
GitHub links, install/installed states. VS Code curated list updated
to match. All new copy translated across 12 locales.

* fix(skills): address catalog review findings

- GitHub metadata fetch timeout drops to 1.5s (under the catalog
  client's 3s deadline) and failed lookups cache briefly (5 min) so
  repeated catalog loads do not re-hit a failing API.
- Disk cache files are written with owner-only permissions (0o600);
  rename preserves the mode.
- loadSource deduplicates concurrent in-flight requests per source and
  the shared isLoadingSource flag now clears only when the last active
  source load finishes.

packages/ui/src/lib/i18n/messages/pt-BR.settings.ts

@@ -865,16 +865,26 @@ export const settingsDict = {
   "settings.skills.catalog.page.mode.manual": "Manual",
   "settings.skills.catalog.page.mode.external": "Externo",
   "settings.skills.catalog.page.title": "Catálogo de habilidades",
+  'settings.skills.catalog.page.subtitle': 'Instale skills prontas de repositórios curados ou adicione sua própria fonte.',
+  'settings.skills.catalog.page.section.sources': 'Fontes',
+  'settings.skills.catalog.page.searchAllPlaceholder': 'Pesquisar skills em todas as fontes…',
+  'settings.skills.catalog.page.search.clear': 'Limpar pesquisa',
+  'settings.skills.catalog.page.source.skillsCount': 'Skills: {count}',
+  'settings.skills.catalog.page.source.stars': 'Estrelas: {count}',
+  'settings.skills.catalog.page.source.updated': 'Atualizado {time}',
+  'settings.skills.catalog.page.source.addOwnTitle': 'Adicionar sua própria fonte',
+  'settings.skills.catalog.page.source.addOwnDescription': 'Qualquer repositório Git com skills',
+  'settings.skills.catalog.page.source.viewRepo': 'Abrir repositório no GitHub',
+  'settings.skills.catalog.page.skill.viewOnGithub': 'Ver skill no GitHub',
+  'settings.skills.catalog.page.list.searchTitle': 'Resultados da pesquisa',
   "settings.skills.catalog.page.section.sourceRepository": "Repositório de origem",
   "settings.skills.catalog.page.field.selectSourcePlaceholder": "Selecionar origem",
   "settings.skills.catalog.page.actions.refreshTitle": "Atualizar",
   "settings.skills.catalog.page.actions.removeCatalogTitle": "Excluir catálogo",
   "settings.skills.catalog.page.actions.addCatalog": "Adicionar catálogo",
   "settings.skills.catalog.page.actions.removeCatalog": "Excluir catálogo",
-  "settings.skills.catalog.page.actions.loadMoreSkills": "Carregar mais habilidades",
   "settings.skills.catalog.page.loading.catalog": "Carregando...",
   "settings.skills.catalog.page.loading.skills": "Carregando habilidades...",
-  "settings.skills.catalog.page.loading.more": "Carregando...",
   "settings.skills.catalog.page.foundCount": "{count} habilidade(es) encontrada(s)",
   "settings.skills.catalog.page.error.catalogTitle": "Erro do catálogo",
   "settings.skills.catalog.page.empty.noSkillsTitle": "Nenhuma habilidade encontrada",
@@ -882,7 +892,6 @@ export const settingsDict = {
   "settings.skills.catalog.page.badge.installed": "instalado ({scope})",
   "settings.skills.catalog.page.badge.notInstallable": "não instalável",
   "settings.skills.catalog.page.badge.unknown": "desconhecido",
-  "settings.skills.catalog.page.byOwnerPrefix": "por",
   "settings.skills.catalog.page.removeDialog.title": "Excluir catálogo",
   "settings.skills.catalog.page.removeDialog.description": "Tem certeza de que deseja excluir este catálogo?",
   "settings.openchamber.passkeys.title": "Chaves de acesso",