Native iPhone port of Factorio 2.0.77

Run the original macOS ARM64 game code on iOS:
- tools/retarget.py: header-only Mach-O retargeting to an iOS dylib
- platform/native: UIKit host and macOS API shims (AppKit for SDL's
  Cocoa backend, CoreGraphics displays, CoreAudio device, Metal device
  properties, Wuffs PNG decoding, Steam and peripheral stubs)
- touch, overlay, iOS keyboard and hardware keyboard input
- tools/build_native.py: build, sign, install, data copy, launch
- docs: build guide, controls, architecture

Also includes the earlier static-translation research (ARM64 -> WASM ->
native) under docs/research, runtime/, tests/ and tools/.

No game files are included; the build reads them from a local install.

tools/package_ios.py

@@ -0,0 +1,36 @@
+#!/usr/bin/env python3
+"""Build and audit an unsigned iOS prototype; does not sign or install it."""
+import hashlib
+import json
+import subprocess
+import zipfile
+from pathlib import Path
+
+root = Path(__file__).resolve().parent.parent
+subprocess.run(["xcodegen", "generate", "--spec", "platform/ios/project.yml"], cwd=root, check=True)
+build = subprocess.run([
+    "xcodebuild", "-quiet", "-project", "platform/ios/FactorioPort.xcodeproj",
+    "-scheme", "FactorioPort", "-sdk", "iphoneos", "-destination", "generic/platform=iOS",
+    "-configuration", "Release", "-derivedDataPath", "build/ios", "CODE_SIGNING_ALLOWED=NO", "build"
+], cwd=root, text=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+(root / "build/ios-build.log").write_text(build.stdout)
+if build.returncode:
+    print(build.stdout[-12000:])
+    raise SystemExit(build.returncode)
+app = root / "build/ios/Build/Products/Release-iphoneos/FactorioPort.app"
+binary = app / "FactorioPort"
+dependencies = subprocess.check_output(["xcrun", "otool", "-L", str(binary)], text=True)
+imports = subprocess.check_output(["xcrun", "nm", "-u", str(binary)], text=True)
+if "steam" in (dependencies + imports).lower():
+    raise RuntimeError("Steam dependency/import found in local single-player target")
+ipa = root / "build/FactorioRNG-unsigned.ipa"
+with zipfile.ZipFile(ipa, "w", zipfile.ZIP_DEFLATED) as archive:
+    for path in sorted(app.rglob("*")):
+        if path.is_file():
+            archive.write(path, Path("Payload") / app.name / path.relative_to(app))
+report = {"status": "pass", "ios_build": "unsigned device build", "device_execution": "not run",
+          "steam_dependency_or_import": False,
+          "binary_sha256": hashlib.sha256(binary.read_bytes()).hexdigest(),
+          "dynamic_dependencies": dependencies.splitlines()[1:], "ipa": str(ipa)}
+(root / "build/ios-verification.json").write_text(json.dumps(report, indent=2) + "\n")
+print(json.dumps(report, indent=2))