Add coherent device profiles and User-Agent spoofing

Device archetypes ensure platform, GPU, resolution, and UA all match
(e.g. Linux profile gets Mesa renderers and X11 UA string). Spoofs
navigator.userAgent, appVersion, and oscpu per container.

inject.js

@@ -155,7 +155,10 @@
       hardwareConcurrency: CONFIG.nav.hardwareConcurrency,
       platform: CONFIG.nav.platform,
       deviceMemory: CONFIG.nav.deviceMemory,
-      maxTouchPoints: CONFIG.nav.maxTouchPoints
+      maxTouchPoints: CONFIG.nav.maxTouchPoints,
+      userAgent: CONFIG.nav.userAgent,
+      appVersion: CONFIG.nav.appVersion,
+      oscpu: CONFIG.nav.oscpu
     };
 
     for (const [prop, value] of Object.entries(navOverrides)) {