Refactor runtime callbacks: pass UpdatedFile via onOutput instead of calling writeFile internally

[Copilot]

Runtime implementations were directly calling EmbedContext.writeFile() to persist file changes, tightly coupling runtimes to the embed context and making it impossible to observe file updates from call sites.

Changes

New UpdatedFile type (runtime.tsx)

export interface UpdatedFile {
  type: "file";
  filename: string;
  content: string;
}

RuntimeContext signature updates

• runCommand: onOutput: (output: ReplOutput | UpdatedFile) => void
• runFiles: onOutput: (output: ReplOutput | UpdatedFile) => void

Worker API (worker/runtime.tsx, *.worker.ts)

• WorkerAPI.runCode / runFile return Promise<void> instead of Promise<{ updatedFiles: Record<string, string> }>
• Workers (pyodide, ruby, jsEval) now call onOutput({ type: "file", filename, content }) per updated file rather than returning a batch record
• WorkerProvider removes writeFile dependency entirely

TypeScript runtime (typescript/runtime.tsx)

• Removed useEmbedContext / writeFile dependency
• Emitted JS files are passed via onOutput and merged locally before forwarding to jsEval.runFiles

Call sites (exec.tsx, repl.tsx)

• Both now intercept output.type === "file" in the callback and call writeFile() themselves, keeping file persistence in the UI layer where it belongs

Tests (tests.ts)

• defineTests drops the filesRef parameter
• "files modified by command/script" tests now assert directly on UpdatedFile items collected from the callback, removing the setTimeout polling hack

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• workers.cloudflare.com
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node node node_modules/.bin/next lint (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

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Status	Name	Latest Commit	Preview URL	Updated (UTC)
✅ Deployment successful! View logs	my-code	ee5ab63	Commit Preview URL Branch Preview URL	Feb 28 2026, 09:26 AM