Function createHelperServer

apps/desktop/src/main/helper/server.ts:89–198

(
  opts: CreateHelperServerOptions,
)

 * surfaced as `ok:false` responses — never silently swallowed.
 */
export function createHelperServer(
  opts: CreateHelperServerOptions,
): Promise<HelperServer> {
  const { socketPath, secret, kernel } = opts

  function buildResponse(req: HelperRequest): Promise<HelperResponse> {
    const version = kernel.version()

    // Auth first: a bad secret must not reach any dispatch path.
    if (req.secret !== secret) {
      return Promise.resolve({
        type: req.type,
        ok: false,
        version,
        error: 'helper: shared secret mismatch',
      })
    }

    // Version handshake: reject incompatible wire versions, but still echo the
    // helper's own version so the client can detect a stale install (B-3).
    if (req.version !== HELPER_PROTOCOL_VERSION) {
      return Promise.resolve({
        type: req.type,
        ok: false,
        version,
        error: `helper: protocol version mismatch (helper ${version}, client ${req.version})`,
      })
    }

    return dispatch(req, version)
  }

  async function dispatch(
    req: HelperRequest,
    version: string,
  ): Promise<HelperResponse> {
    try {
      switch (req.type) {
        case 'ping':
        case 'getVersion':
          return { type: req.type, ok: true, version }
        case 'startKernel': {
          const { binaryPath, homeDir, configPath } = req as StartKernelRequest
          const result = await kernel.start({ binaryPath, homeDir, configPath })
          return { type: req.type, ok: true, version, running: result.running }
        }
        case 'stopKernel':
          await kernel.stop()
          return { type: req.type, ok: true, version }
        case 'status': {
          const result = kernel.status()
          return { type: req.type, ok: true, version, running: result.running }
        }
      }
    } catch (err) {
      // Surface (never swallow) any privileged-side failure to the client.
      return {
        type: req.type,