Add UIAutomation background injection for Roblox Studio

- bg_inject.ps1: PowerShell UIAutomation script that finds Studio command bar by AutomationId and injects Lua code without window focus
- bg_inject.py: Python wrapper for bg_inject.ps1
- bg_inject_uia2.ps1: Discovery/debugging script for finding Studio UI controls
- inject_full_gta.py: 7-step GTA city + COD weapons + enemies injection using background API
- inject_gta_bg.py: Alternative multi-file GTA injection loader

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

bg_inject.py

@@ -0,0 +1,57 @@
+"""
+Background injection into Roblox Studio via UI Automation.
+Works when Studio is minimized, behind other windows, or in background.
+No user interaction required.
+"""
+import subprocess, sys, os, time
+
+PS_SCRIPT = r"C:\Users\Admin\bg_inject.ps1"
+
+def inject(code):
+    """Inject Lua code into Roblox Studio command bar in the background."""
+    # Write code to temp file to avoid quoting issues
+    tmp = os.path.join(os.environ["TEMP"], "rbx_bg_inject.lua")
+    with open(tmp, "w", encoding="utf-8") as f:
+        f.write(code)
+
+    result = subprocess.run(
+        ["powershell", "-ExecutionPolicy", "Bypass", "-File", PS_SCRIPT, "-File", tmp],
+        capture_output=True, text=True, timeout=30
+    )
+
+    output = result.stdout.strip()
+    error = result.stderr.strip()
+
+    if "OK" in output:
+        return True, output
+    else:
+        return False, f"{output}\n{error}"
+
+def inject_multi(scripts, label=""):
+    """Inject multiple scripts sequentially."""
+    for i, (name, code) in enumerate(scripts, 1):
+        total = len(scripts)
+        prefix = f"[{label}] " if label else ""
+        print(f"  {prefix}[{i}/{total}] {name}...", end="", flush=True)
+
+        ok, msg = inject(code)
+        if ok:
+            print(" OK")
+        else:
+            print(f" FAILED: {msg}")
+            return False
+        time.sleep(2.5)  # Wait for Studio to process
+    return True
+
+if __name__ == "__main__":
+    if len(sys.argv) > 1:
+        # Inject a file
+        path = sys.argv[1]
+        with open(path, "r", encoding="utf-8") as f:
+            code = f.read()
+        ok, msg = inject(code)
+        print(msg)
+    else:
+        # Test
+        ok, msg = inject('print("BG_INJECT_TEST_OK")')
+        print(msg)