Avoid QuickJS bytecode and use plain JS instead

Turns out the format is too volatile for it to be a good idea to use it
in this context.

.gitignore

@@ -1,4 +1,4 @@
-/app/agent.qjs
+/app/agent.js
 /app/agent/node_modules/
 /cryptoshark.pro.user
 /ext/frida-core/

README.md

@@ -32,10 +32,9 @@ Run the `build` script.  This will output a binary at:
 
 Run the `bootstrap` script and then open `cryptoshark.pro` in Qt Creator.
 
-### Building agent.qjs
+### Building agent.js
 
-This is the bytecode representation of the JavaScript that Cryptoshark injects
-into target processes.
+This is the instrumentation code that Cryptoshark injects into target processes.
 
 For a one-off build:
 
@@ -48,7 +47,7 @@ And to watch while developing:
     $ npm run watch
 
 This will monitor the TypeScript source code and incrementally compile
-`app/agent.qjs`. Note that the agent is included as a resource, so remember to
+`app/agent.js`. Note that the agent is included as a resource, so remember to
 `build`.
 
 ## Building a portable binary