fix: correct handling of singleProjectMode in emulatorsActuate

This change fixes an issue in the `emulatorsActuate` function in `src/init/features/emulators.ts` where the `singleProjectMode` property was not being handled correctly. A specific condition has been added to ensure that this boolean value is assigned properly, preventing a runtime error. This resolves the issue that was causing the code to be 'mangled'.

Author: google-labs-jules[bot]

src/init/features/emulators.ts

@@ -120,6 +120,8 @@ export async function emulatorsActuate(setup: Setup, config: Config): Promise<vo
     const key = emulatorName as keyof EmulatorsConfig;
     if (key === "ui") {
       emulatorsConfig.ui = { ...emulatorsConfig.ui, ...emulatorsInfo.config.ui };
+    } else if (key === "singleProjectMode") {
+      emulatorsConfig.singleProjectMode = emulatorsInfo.config[key];
     } else if (emulatorsInfo.config[key]) {
       emulatorsConfig[key] = { ...emulatorsConfig[key], ...emulatorsInfo.config[key] };
     }