Add current Xquik MCP seed and return import errors

[kriptoburak]

Summary

• Rebuild on current main at 50edf754 with no stale README history.
• Add the current com.xquik/mcp remote server seed.
• Record version 2.6.0 and the canonical GitHub repository ID.
• Include the Streamable HTTP endpoint and optional API-key metadata.

Independent Repository Fix

ImportSeedFile declared an error return but terminated the process on read failure. It now returns contextual wrapped errors for callers to handle. The importer also rejects typed JSON failures instead of returning partial data as success. Three regression tests cover missing files, invalid typed JSON, and the current Xquik seed contract.

Validation

• Go 1.23.12: go test -race ./... and go vet ./...
• Go 1.26.5: go test -race ./... and go vet ./...
• jq empty data/seed_2025_05_16.json
• Exactly 1 com.xquik/mcp seed record
• Seed metadata matches the live public server.json
• Official GitHub repository ID verified
• Xquik MCP docs return HTTP 200
• Unauthenticated MCP probe returns the expected HTTP 401
• git diff --check, git fsck, and merge-tree checks
• Exactly 1 GitHub-verified signed commit on current upstream main

The branch changes only the Xquik seed and tested importer error handling.

Xquik is an independent third-party service. Not affiliated with X Corp. "Twitter" and "X" are trademarks of X Corp.

[kriptoburak]

Upstream force-pushed main again, so I rebuilt the branch from current base 50edf754. The PR now contains one GitHub-verified signed commit and exactly three focused files: the current Xquik 2.6.0 seed, importer error handling, and regression tests. The stale README delta is gone.

Go 1.23.12 and Go 1.26.5 race tests and vet checks pass. JSON, live server-card, repository-ID, link, expected 401, diff, object, and merge-tree checks also pass.

Exact head: 2d477b17fe84fdebaa1c3fd6f0a8d2f6ddaf3a01. Ready for maintainer review.