feat(rsc): register federation manifest data at runtime

[ScriptedAlchemy]

Summary

• Add the host-side mf-rsc-registration-runtime-plugin.js that reads manifest RSC metadata and registers it into __webpack_require__.rscM
• Stage manifest payloads from runtime hooks, install virtual modules for exposed/shared references and actions, and refresh registration state deterministically
• Add runtime-plugin verification coverage and keep this PR scoped to consuming manifest data that already exists in the earlier stack PRs

Stack

Current stack, bottom to top:

• #12977 feat(mf): layer-aware sharing and runtime scope-array support
• #13203 feat(mf): emit RSC metadata in federation manifests
• #13204 feat(rsbuild): add RSC federation host/remote example
• #13208 feat(rsbuild): add RSC federation module patterns
• #13215 feat(rsc): register federation manifest data at runtime <- this PR

Why This PR Exists

This is the runtime integration step for the stack. It consumes the manifest contract from #13203 and the example surface from #13204 and #13208, and registers federated RSC references at runtime without leaking __webpack_require__ globally.

References

• Manifest producer contract: #13203

[cursor]

Cursor Agent can help with this pull request. Just @cursor in comments and I'll start working on changes in this branch.
_{Learn more about Cursor Agents}

[github-actions]

📦 Binary Size-limit

Comparing 0692ec7 to chore(ci): eco benchmark compare base optimize (#13360) by pshu

❌ Size increased by 115.00KB from 49.01MB to 49.12MB (⬆️0.23%)

[cloudflare-workers-and-pages]

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[github-actions]

Rsdoctor Bundle Diff Analysis

Found 5 projects in monorepo, 0 projects with changes.

📊 Quick Summary

Project	Total Size	Change
react-10k	5.7 MB	0
react-1k	826.2 KB	0
react-5k	2.7 MB	0
rome	984.2 KB	0
ui-components	2.3 MB	0

Generated by Rsdoctor GitHub Action

[codspeed-hq]

Merging this PR will not alter performance

✅ 16 untouched benchmarks
⏩ 3 skipped benchmarks¹

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_{Comparing cursor/rsc-module-federation-registration-0f08 (0692ec7) with cursor/rsc-federation-module-patterns-42fd (a9cb9e8)}

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩