[rqzbeh]

Fixes #11100.

Summary

1. Replaces the hardcoded 9-provider array in omniroute_web_search MCP tool's webSearchInput schema with z.enum(getActiveSearchProviders()).
2. Adds getActiveSearchProviders(blockedProviders?: string[]) to open-sse/config/searchRegistry.ts, which dynamically returns active registered search provider IDs and filters out any disabled or blocked providers (via isProviderBlockedByIdOrAlias).
3. Updates handleWebSearch in open-sse/mcp-server/server.ts signature to accept provider?: string.
4. Adds automated contract unit test tests/unit/mcp-web-search-provider-enum-contract.test.ts.

[diegosouzapw]

Closing with credit — verified subsumed against the current tip:

• The dynamic MCP web_search provider enum shipped via fix(mcp): dynamically generate web search provider enum from registry #10209 (providerEnums.getActiveSearchProviders(), wired into webSearchInput).
• blockedProviders filtering for search shipped today via fix(search): enforce blockedProviders setting on search endpoint (#11100) #11125 (getAllSearchProviders(blockedProviders) + the /v1/search route wiring).
• This PR's residual is a getActiveSearchProviders() in searchRegistry.ts that nothing calls (the tools.ts import was removed by its own follow-up commit).

Remaining known gap (filed mentally as backlog): the MCP enum is built statically at module scope, so runtime-blocked providers still appear in the schema — a real fix needs runtime-schema plumbing, which is a separate design. Thank you @rqzbeh — the endpoint half of #11100 landed through your #11125!