[MCP] feat(catalog-mcp): build tooling, configureMcpCatalog, the v1.0 entry point and the samples on it

[josemontespg]

Summary

Prepares @a2ui/catalog-mcp for the v1 MCP catalog: the build and test tooling the package needs from here on, configureMcpCatalog, the single host entry point that replaces createMcpCatalogFunctions, and the two community MCP sample clients moved to it. The McpApp component and mcpCatalog follow in #2799; this PR carries the host-side half of the MCP Apps flow (onMcpAppResource, ui:// resource extraction) so that callMcpTool is complete when the component lands.

The entry point now targets A2UI v1.0. CallMcpToolImplementation ships pre-constructed and reads the host configuration when it runs, so there is no processor-before-catalog ordering; a host registers it under MCP_CATALOG_ID and calls configureMcpCatalog({getMcpClientForTool, processor, sandbox?}) once.

Changes

• package.json, karma.conf.cjs, tsconfig.test.json, eslint.config.mjs, .gitignore, scripts/build-sandbox.mjs, scripts/build-test-fixtures.mjs: wireit build (copy of the v1 catalog.json and of typescript/catalogs/shared/, esbuild bundle of the sandbox proxy into dist/sandbox/), Karma browser tests next to the Node tests, publication metadata. scripts/copy-catalog.js is gone; the fixtures script is a no-op until [MCP] Add the McpApp universal component and mcpCatalog to @a2ui/catalog-mcp #2799 adds tests/fixtures/apps/.
• src/mcp_catalog_config.ts: configureMcpCatalog (MCP client resolver, processor, defaultVersion, onMcpAppResource, sandbox location).
• src/functions/callMcpTool.ts: bound to the host configuration; extracts ui:// MCP App resources (text/html;profile=mcp-app) into McpAppResourcePayload; arguments also accepts a function call that returns the arguments object.
• src/catalog.ts, src/index.ts: MCP_CATALOG_ID for catalogs/mcp/v1/catalog.json; the entry point exports MCP_CATALOG_ID, CallMcpToolImplementation, configureMcpCatalog and their types.
• README.md, CHANGELOG.md: setup, configureMcpCatalog, sandbox asset.
• samples/community/mcp/a2ui-over-mcp-{filesystem,recipe}/client: register CallMcpToolImplementation (the filesystem sample next to its own data functions) and configure the host with configureMcpCatalog; resolve @a2ui/catalog-mcp, @a2ui/lit and @a2ui/web_core from the monorepo dist/ instead of compiling the catalog from source against the npm packages (TODO Clean up folder samples/community. #1698). .github/workflows/community_code.yml builds those packages at the repository root first.

Verification

• yarn workspace @a2ui/catalog-mcp test: 82 Node tests, 141 Karma tests (shared sandbox).
• yarn test in both sample clients against a fresh @a2ui/catalog-mcp build (64 and 11 tests).
• ./scripts/fix_format.sh --check, python3 scripts/fix_licenses.py --check.

Related to #3157

[gemini-code-assist]

Code Review

This pull request updates the A2UI MCP catalog to target protocol v1.0, refactoring the serialization API by introducing Catalog.fromJson, Catalog.toJson, and Catalog.validationSchema to replace deprecated methods. It removes five data transformation functions to the filesystem sample, refactors callMcpTool to support MCP App resource extraction, and introduces a shared double-iframe sandbox proxy to isolate untrusted web content. The review feedback suggests normalizing MIME types in isMcpAppMimeType to handle spacing variations and replacing a deprecated Catalog.fromSchema call with Catalog.fromJson in the test suite.