ci(platform): sync asyncapi.json from production every week

[amitbardos]

Stacked on #313. Split out of #313 so the docs and getSession there don't wait on a workflow review.

What

.github/workflows/sync-asyncapi.yml runs weekly on Mondays at 06:00 UTC and on workflow_dispatch:

1. It runs npm run sync:asyncapi against https://app.base44.com/api/asyncapi.json, then gen:events.
2. If packages/platform/asyncapi.json or builder.events.generated.ts changed, it runs create-docs and npm test for the Platform SDK.
3. It opens or updates one rolling PR on bot/platform-asyncapi-sync. The branch is rebuilt from main on every run, so it never conflicts.
4. When nothing changed, it closes a leftover sync PR.

It uses only what the repo already uses: the pinned actions/checkout and actions/setup-node, the mandatory Wix gateway proxy, and the runner's gh. No new dependencies. CI checks the proxy step with check_wix_proxy_steps.py (check-wix-proxy.yml).

Before merging

base44-dev/apper#29607 is deployed: production serves the full document, and it's identical to the asyncapi.json committed in #313, so a run today finds no diff. After merging, trigger the workflow once by hand.

🤖 Generated with Claude Code

[github-actions]

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npm i @base44-preview/sdk@0.8.53-pr.318.d8cd2bb

Prefer not to change any import paths? Install using npm alias so your code still imports @base44/sdk:

npm i "@base44/sdk@npm:@base44-preview/sdk@0.8.53-pr.318.d8cd2bb"

Or add it to your package.json dependencies:

{
  "dependencies": {
    "@base44/sdk": "npm:@base44-preview/sdk@0.8.53-pr.318.d8cd2bb"
  }
}

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_{Preview published to npm registry — try new features instantly!}

[amitbardos]

Folded into #313: production already serves the full AsyncAPI document, so the workflow no longer needs to wait.