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/startup_inventory.py

@@ -0,0 +1,28 @@
+"""Export the observed startup frontier; never equates discovery with runnable code."""
+import json
+import re
+from pathlib import Path
+
+bundle = json.loads(Path('evidence/factorio-functions-final.json').read_text())
+record = next(r for r in bundle['records'] if r['operation'] == 'analyze_function'
+              and r['parameters']['procedure'] == '0x100161584')
+native = record['normalized_result']
+callees = []
+for callee in native['callees']:
+    symbol = callee['name']
+    route = 'exclude-optional-steam' if 'Steam' in symbol else 'host-abi-adapter' if symbol.startswith('imp___stubs') else 'pending-lift'
+    callees.append({'address': callee['address'], 'symbol': symbol,
+                    'planned_route': route, 'route_authority': 'analyst planning from symbol identity'})
+indirect = [line for line in native['assembly'] if re.search(r': blr\s', line)]
+result = {'status': 'not-runnable', 'root': native['procedure']['name'],
+          'root_address': '0x100161584', 'evidence_id': record['evidence_id'],
+          'observed_direct_callees': len(callees), 'observed_basic_blocks': len(native['basic_blocks']),
+          'observed_indirect_call_sites': indirect, 'callees': callees,
+          'limitations': ['This is one observed function frontier, not a transitive closure.',
+                         'Hopper does not expose complete body ranges or all indirect targets.',
+                         'The straight-line lifter cannot yet compile this startup function.',
+                         'Graphical startup includes inlined Steam initialization; changing the factory alone is insufficient.']}
+out = Path('build/startup'); out.mkdir(parents=True, exist_ok=True)
+(out / 'frontier.json').write_text(json.dumps(result, indent=2) + '\n')
+print(json.dumps({key: result[key] for key in ['status', 'root_address', 'evidence_id',
+                 'observed_direct_callees', 'observed_basic_blocks']}, indent=2))