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/loader_inventory.py

@@ -0,0 +1,36 @@
+#!/usr/bin/env python3
+"""Summarize observed REA loader frontiers without inferring graph closure."""
+import argparse
+import json
+from pathlib import Path
+
+ROOTS = ['0x1014c93f8', '0x1014c9618', '0x1000fa1d0', '0x1014c6aac']
+TARGET = '2cb4de127b50d54c6c5666acfef2263fae16d11a3361ad39353ecf8a66a4d9c7'
+parser = argparse.ArgumentParser(description=__doc__)
+parser.add_argument('bundle', type=Path)
+args = parser.parse_args()
+records = json.loads(args.bundle.read_text())['records']
+records = [r for r in records if r.get('authority') == 'shipped-artifact'
+           and r.get('confidence') == 'observed'
+           and r.get('subject', {}).get('digest', {}).get('sha256') == TARGET]
+roots = []
+for address in ROOTS:
+    selected = [r for r in records if r.get('parameters', {}).get('procedure') == address]
+    calls = [r for r in selected if r['operation'] == 'procedure_callees']
+    if not calls:
+        raise ValueError('Missing observed call frontier for ' + address)
+    record = calls[-1]
+    info = [r['normalized_result'] for r in selected if r['operation'] == 'procedure_info']
+    assembly = [r for r in selected if r['operation'] == 'procedure_assembly']
+    roots.append({'address': address, 'direct_callees': record['normalized_result'],
+                  'direct_callee_count': len(record['normalized_result']),
+                  'evidence_id': record['evidence_id'], 'relationship_coverage': record.get('relationship_coverage'),
+                  'procedure': info[-1] if info else None,
+                  'unresolved_indirect_sites': [line for line in assembly[-1]['normalized_result'].splitlines()
+                                               if ': blr ' in line or ': br ' in line] if assembly else None,
+                  'scope': 'observed immediate frontier; not transitive dependency closure'})
+output = Path('build/startup/loader-frontier.json')
+output.parent.mkdir(parents=True, exist_ok=True)
+output.write_text(json.dumps({'status': 'not-runnable', 'arm64_sha256': TARGET,
+                             'roots': roots}, indent=2) + '\n')
+print('PASS: observed direct call frontiers:', ', '.join(str(r['direct_callee_count']) for r in roots))