feat: add the apify-factory review workflow

[mfori]

Adds the reusable workflow that runs the apify-factory AI review and auto-approval for the repositories that opt in.

• The pipeline lives in the internal apify/ai-developer, which public repositories cannot call, so every review run in them failed before starting.
• This workflow holds only the job wiring: a cheap lookup of an existing bot approval on each push, and the review job, which checks ai-developer out with the bot's token and runs its auto-approve action from that checkout.
• Each opted-in repository keeps a short stub that calls this workflow; the pipeline code, prompts and gates stay internal.

Context: https://github.com/apify/apify-sdk-js/actions/runs/38864655263

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Generated by Claude Code

[mfori]

apify-pr-toolkit fails with "Missing org-github-token input!" — that is the repo-level toolkit workflow still passing the old inputs, red on every PR here (also #331). It is fixed by #334, which removes those workflows; the org ruleset's apify-pull-request-toolkit check covers the toolkit instead. Not porting it here to keep this PR to the new workflow.

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Generated by Claude Code