feat: add Quick Add dialog to Connect MCP Server form for open MCP servers only.

[marekdano]

Summary

Implements a "Quick Add" dialog on the Add MCP Server flow (#4681): a curated shortlist of catalog servers you can pick from, which pre-fills the standard Connect MCP Server form.

• Added QuickAddServerDialog — a radiogroup grid of curated catalog cards (logo/name/description), with Cancel/Continue actions and a link out to the full server catalog.
• Curated list (src/config/quickAddServers.ts): deepwiki, exa-search, ferryhopper, hugging-face, remote-mcp, aws-knowledge, context-awesome, javadocs — all auth_type: "Open", no credentials required. The Figma design's original 8 servers are all OAuth2.1-only, and OAuth catalog registration still dead-ends today (blocked upstream on #5967); this swap keeps the feature fully functional end-to-end now, with no backend changes required.
• Quick Add itself is scoped to no-auth servers, but it isn't an OAuth-only vs. everything-else split: submission goes through the existing /gateways create flow, so the picked defaults land in the same MCPServerForm used everywhere else — including AdvancedSettings, where a user can still add an API token/bearer auth (or basic/custom headers) by hand for a server that needs one. Only the automated OAuth handshake is unbuilt; manual API-key/token auth already works today.
• useMCPServerForm gains an optional initialValues param so a picked catalog entry (name/url/description/transport) seeds a fresh create-mode form, fully editable before the server is actually created.
• New "Quick add from catalog" trigger on MCPServerForm, next to the existing catalog link.
• Extracted CatalogLogo out of CatalogResults into a shared component (src/components/server-catalog/CatalogLogo.tsx) so both surfaces render logos identically. Also fixed a latent bug in its URL validator: root-relative bundled asset paths (e.g. /static/catalog-icons/deepwiki.png) were being rejected as invalid URLs and silently falling back to the generic icon.
• i18n: new mcpServer.quickAdd.* keys added to en-US, es-ES, and pt-BR.

Test plan

• npx tsc -b --noEmit — clean
• npm run lint — clean
• npx vitest run — 3232 passed, 1 skipped (198 files), including the i18n locale-parity check
• npx playwright test e2e/quick-add-server.spec.ts — open trigger → pick a curated server → Continue → form pre-filled (name/url/description/transport) → submit → POST /gateways fires with the expected body; and the "browse full catalog" link closes the dialog/form and navigates away
• npx playwright test e2e/server-catalog.spec.ts — re-ran to confirm the CatalogLogo extraction didn't regress the existing catalog page (10/10 pass)

DEMO

add-quick-dialog-mcp-servers_dsxZtQCv.mp4

[a-effort]

Nice work getting this kicked off! There are some changes to the user experience to implement before this is merged (Figma that I'll add detail for.