Feat/issue 93 runtime compat

[Oluwasuyi-Oluwatimilehin-Daniel]

#closes #93

Summary

Addresses #93 by setting up a dedicated multi-runtime verification matrix using Vitest Workspaces. This guarantees the universal SDK claim remains functional and prevents Node-only globals or modules from creeping into browser/edge contexts.

What Changed?

• Vitest Configuration: Separated core test parameters out into a new vitest.workspace.ts file.
• Environment Matrix: Configured three isolated test workspaces:
  • node: Handles standard package unit tests (excludes compat folders).
  • browser: Uses jsdom to verify execution inside standard web browsers.
  • edge: Leverages vitest-environment-edge-runtime to mirror V8 engine restrictions (Cloudflare Workers/Vercel Edge).
• Test Implementation: Added tests/compat/browser/browser.test.ts and tests/compat/edge/edge.test.ts to test client initialization and custom fetch execution paths under isolated constraints.
• CI Workflow Update: Integrated pnpm test:run directly into the .github/workflows/ci.yml file to block broken code architectures at the gate.

Acceptance Criteria Verification

• Compatibility tests execute successfully in a Node runtime environment.
• Compatibility tests execute successfully in a browser-like (jsdom) runtime environment.
• Compatibility tests cover a custom fetch mock/transport.
• SDK imports do not throw errors or demand Node-only globals in browser-like environments.
• CI pipeline successfully running all suites prior to public API serialization checks.

How to Test Locally

1. Run pnpm install to grab the new edge-runtime testing utilities.
2. Run pnpm test:run (or pnpm test).
3. Observe all 3 project badges ([node], [browser], [edge]) reporting successful execution assertions.
   #closes