Fix CI failure: migrate from npm to pnpm workspace

[Copilot]

The repository uses pnpm's workspace:* protocol for internal dependencies, but CI workflows were configured for npm, which doesn't support this protocol. This caused npm ci to fail with Unsupported URL Type "workspace:".

Changes

Package manager configuration:

• Add pnpm-workspace.yaml and pnpm-lock.yaml
• Remove package-lock.json
• Add packageManager: "pnpm@10.28.2" to package.json

CI workflows (.github/workflows/):

• Enable Corepack before Node.js setup
• Change cache from npm to pnpm
• Replace npm ci → pnpm install --frozen-lockfile
• Replace npm run → pnpm run

Updated workflows: ci.yml, publish.yml, release.yml, azure-functions.yml

Documentation:

• Update README.md and CONTRIBUTING.md to use pnpm commands

Example workspace dependency

{
  "dependencies": {
    "@plures/praxis-core": "workspace:*"
  }
}

This syntax requires pnpm; npm treats it as an invalid protocol.

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[kayodebristol]

Draft PR noted by automated sweep. If this is ready, mark it Ready for review; otherwise please add the remaining checklist items/blockers. [@copilot] can help finalize when ready.

[Copilot]

Draft PR noted by automated sweep. If this is ready, mark it Ready for review; otherwise please add the remaining checklist items/blockers. [@copilot] can help finalize when ready.

This PR is ready for review. All work is complete:

✅ Root cause fixed: migrated from npm to pnpm (commits 1483cf6-a0a4547)
✅ All CI workflows updated (.github/workflows/)
✅ Documentation updated (README.md, CONTRIBUTING.md)
✅ Tested locally: build, test, and scan:rules all pass
✅ Code review and security scan completed

The changes fix the CI failure on the base branch where npm ci failed due to pnpm's workspace:* protocol. This is a stacked PR on the dependabot branch, so CI won't run automatically, but the fixes are verified locally and ready for merge.

[kayodebristol]

This PR is currently Draft.\n\nMinimal next steps:\n- Mark as Ready for review when safe\n- Ensure CI is green\n- Request review / address feedback\n\nOnce checks are green + required reviews are satisfied, we can squash merge.

[kayodebristol]

This PR is currently Draft.

Minimal next steps:

• Mark as Ready for review when safe
• Ensure CI is green
• Request review / address feedback

Once checks are green + required reviews are satisfied, we can squash merge.

[kayodebristol]

Closing as superseded by #155 (single consolidated fix for the Node 18/20 CI + workspace:* issue). If we need to resurrect any approach from this PR, we can reopen.