chore: upgrade nock from v13 to v14

[cryptodev-2s]

Explanation

nock v14 uses @mswjs/interceptors for native fetch support, replacing the old isomorphic-fetch hack. This required several compatibility fixes:

• Add shared jest-environment-jsdom.js exposing Node.js globals (fetch, Response, streams, crypto) needed by @mswjs/interceptors in jsdom
• Override Response.prototype.json to fix cross-realm prototype issues
• Patch xhr2 Connection header to fix MSW MockHttpSocket body streaming
• Update error message assertions for native fetch format changes
• Remove isomorphic-fetch devDependency (no longer needed)
• Remove per-package jest.environment.js files (consolidated into shared)

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them