fix(fifa17): guard missing store category resolution

Port the PROVEN empty-"My Packs" resolver crash-guard into the canonical
autopatch.py /proc-mem patcher. When no `mypacks` purchase group exists, a
fresh FIFA 17 client resolves category id -1; CardsDLL FUN_1800147f0 at RVA
0x14858 (`JNZ 0x14869`, bytes 75 0f) treats every non-zero category as
resolvable, calls FUN_180014420, gets NULL, and dereferences [NULL+0x48] at
0x180014882 (0xC0000005). Rewriting JNZ->JG (7f 0f) preserves positive-category
resolution (EDI>0) while routing zero/negative categories to the existing
Browse/list-all path -> no NULL lookup, no crash, Store opens on Browse Packs.

- STORE_PATCHES_GUARDED table pins RVA 0x180014858 orig 75 0f -> patch 7f 0f.
- Applied every tick, fail-closed via guarded_action(): apply only when the
  live bytes are the known original; no-op when already patched; SKIP+log an
  unrecognised CardsDLL build (never blindly overwritten).
- Runtime watch loop moved under `if __name__ == "__main__"` so the module
  imports cleanly for unit testing; script behavior is unchanged. Existing
  ProtoSSL cert-gate and STORE_PATCHES enforcement are byte-identical (indent
  only).
- test_autopatch_guard.py: pure test covering PATCH/NOOP/SKIP and pinning the
  exact guarded RVA/bytes.

Proven on the tested build (CardsDLL 4706a881...) by a clean fresh-process
no-sentinel A/B (R1). Dormant while the backend active-sentinel is present.
See docs/plans/FIFA17_EMPTY_MYPACKS_CLIENT_FIX.md PART IV.

fifa17-recon/tools/test_autopatch_guard.py

@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+"""Pure unit test for the empty-My-Packs store resolver guard in autopatch.py.
+
+Covers the fail-closed guard decision (original -> PATCH, already-patched -> NOOP,
+unknown -> SKIP) and pins the guarded patch table to the exact RVA/bytes proven on
+the tested FIFA 17 build (JNZ 0x14869 -> JG 0x14869 at CardsDLL RVA 0x14858).
+
+Run: python3 test_autopatch_guard.py
+"""
+import os
+import sys
+
+sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
+import autopatch  # importable: runtime loop is guarded by `if __name__ == "__main__"`
+
+GUARD_VA = 0x180014858
+ORIG = bytes.fromhex("750f")   # JNZ 0x14869
+PATCH = bytes.fromhex("7f0f")  # JG  0x14869
+
+
+def test_table_exact():
+    assert autopatch.STORE_PATCHES_GUARDED == {GUARD_VA: (ORIG, PATCH)}, \
+        autopatch.STORE_PATCHES_GUARDED
+    # Byte-level pin so a bad hex literal cannot slip through.
+    assert ORIG == b"\x75\x0f" and PATCH == b"\x7f\x0f"
+
+
+def test_decision():
+    assert autopatch.guarded_action(ORIG, ORIG, PATCH) == "patch"   # apply
+    assert autopatch.guarded_action(PATCH, ORIG, PATCH) == "noop"   # already patched
+    assert autopatch.guarded_action(b"\x00\x00", ORIG, PATCH) == "skip"  # build mismatch
+    assert autopatch.guarded_action(b"\x90", ORIG, PATCH) == "skip"      # wrong length
+
+
+if __name__ == "__main__":
+    test_table_exact()
+    test_decision()
+    print("OK: autopatch guard table + fail-closed decision (PATCH/NOOP/SKIP)")