feat: add parallel Vitest test suite and cross-repo CI trigger (issue #49)

[aditya-8787]

What this PR does

Foundation PR for improving test reliability across metacall/protocol,
metacall/faas and metacall/deploy as discussed in issue #49 .

Changes

File	What
vitest.config.js	Vitest config targeting test/*.vitest.ts only
test/protocol.vitest.ts	First TypeScript test file — 11 tests, all passing
package.json	Added test:vitest and test:coverage scripts
.github/workflows/ci.yml	Vitest blocking + Mocha non-blocking + dispatch trigger

Approach

1. Parallel test suite
New tests live in test/*.vitest.ts. Mocha picks up dist/test/*.js so
the two runners never conflict. Mocha stays non-blocking
(continue-on-error: true) since CI is already known fragile. Old tests
removed only once full TypeScript coverage is verified — clean cut, not
a dragged-out migration.

2. Cross-repo CI trigger
Added repository_dispatch: protocol-updated to CI so faas and deploy can
be pinged when protocol master changes. Downstream workflows that install
protocol from GitHub master instead of pinned npm are follow-up PRs in
those repos.

3. Secrets handling
pull_request_target + protected environment approach for METACALL_API_KEY
belongs in the deploy repo — will be handled there.

Test results

✓ index module loads without errors
✓ has correct package name
✓ has a valid semver version string
✓ deployment module loads
✓ login module loads
✓ token module loads
✓ plan module loads
✓ signup module loads
✓ language module loads
✓ package module loads
✓ protocol module loads

Test Files: 1 passed | Tests: 11 passed | Duration: 539ms

What comes next

• Workflow in metacall/faas listening for protocol-updated, installing
  protocol from GitHub master instead of pinned npm
• Same for metacall/deploy + secrets handling with protected environments
• More .vitest.ts tests covering protocol logic and edge cases

[aditya-8787]

@viferga as we discussed, I have started working on the testing improvements
for issue #49. I have set up the parallel Vitest test suite alongside the
existing Mocha tests with 11 passing tests covering all source modules. I have
also added the repository_dispatch trigger for cross-repo CI. I am raising the
PR now and will follow up with the downstream workflows in faas and deploy repos
as the next steps. Please have a look when you get a chance. Thanks

[viferga]

This is wrong. I can't merge it.

[aditya-8787]

@viferga Before I proceed further, I wanted to share my plan
for the next steps and get your confirmation that I am going in the
right direction.

Here is what I am planning next:

1. protocol repo — Add a trigger-downstream job to the existing CI
   that pings metacall/faas and metacall/deploy via repository_dispatch
   after every master push, so they can test against latest protocol
   instead of a pinned version.

2. faas repo — Add a small workflow that listens for the
   protocol-updated event, replaces the pinned protocol version with
   metacall/protocol#master and runs existing tests.

3. deploy repo — Same as faas, plus split into two jobs: unit tests
   run on all PRs normally, integration tests only run when a maintainer
   applies a safe-to-test label so METACALL_API_KEY is never exposed to
   fork PRs.

Does this align with what you had in mind? Let me know if I should
approach anything differently before I start. Thanks

[viferga]

You added vitest but it was not strictly necessary. What we needed is adding a proper testing that triggers deploy and faas repositories. We have added them recently with @Priyanshu-u07