Add scripts/check-vba-roundtrip.sh: verify VBA preservation on a real file

Builds a macro-enabled .xlsm with a fake xl/vbaProject.bin, runs it through
`gridcraft-cli run`, and asserts the blob comes back byte-identical with the
macro-enabled content type and vbaProject relationship intact — the
open → edit → save path a user would exercise by hand.

scripts/check-vba-roundtrip.sh

@@ -0,0 +1,86 @@
+#!/usr/bin/env bash
+# Verify that GridCraft preserves VBA macros (xl/vbaProject.bin) across a round-trip.
+#
+#   bash scripts/check-vba-roundtrip.sh
+#
+# What it does: builds a macro-enabled .xlsm containing a fake vbaProject.bin, runs it
+# through `gridcraft-cli run`, and checks the blob comes back byte-identical with the
+# macro-enabled content type + relationship intact. Requires python3 (zip) and a
+# release build of gridcraft-cli.
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "$0")/.." && pwd)"
+CLI="$ROOT/target/release/gridcraft-cli.exe"
+[ -x "$CLI" ] || CLI="$ROOT/target/release/gridcraft-cli"
+PYTHON="${PYTHON:-python3}"
+
+# A fresh temp dir. Under Git Bash (MSYS) the shell's /tmp is not a path the native
+# Windows python.exe or the engine understand when embedded in JSON, so convert to the
+# platform-native form when cygpath is available.
+TMP="$(mktemp -d)"
+if command -v cygpath >/dev/null 2>&1; then
+  NATIVE_TMP="$(cygpath -w "$TMP")"   # for python (native Windows path)
+  JSON_TMP="$(cygpath -m "$TMP")"     # for JSON params (forward slashes: no escaping)
+else
+  NATIVE_TMP="$TMP"
+  JSON_TMP="$TMP"
+fi
+
+# 1. Build a macro-enabled .xlsm with a fake OLE/CFB vbaProject.bin.
+"$PYTHON" - "$NATIVE_TMP" <<'PY'
+import zipfile, os, sys
+tmp = sys.argv[1]
+main_ct = "application/vnd.ms-excel.sheet.macroEnabled.main+xml"
+ct = ('<?xml version="1.0"?><Types xmlns="http://schemas.openxmlformats.org/package/2006/content-types">'
+      '<Default Extension="xml" ContentType="application/xml"/>'
+      '<Default Extension="rels" ContentType="application/vnd.openxmlformats-package.relationships+xml"/>'
+      f'<Override PartName="/xl/workbook.xml" ContentType="{main_ct}"/>'
+      '<Override PartName="/xl/worksheets/sheet1.xml" ContentType="application/vnd.openxmlformats-officedocument.spreadsheetml.worksheet+xml"/>'
+      '<Override PartName="/xl/vbaProject.bin" ContentType="application/vnd.ms-office.vbaProject"/></Types>')
+root = ('<?xml version="1.0"?><Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">'
+        '<Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument" Target="xl/workbook.xml"/></Relationships>')
+wb = ('<?xml version="1.0"?><workbook xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" '
+      'xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships">'
+      '<sheets><sheet name="Sheet1" sheetId="1" r:id="rId1"/></sheets></workbook>')
+rel = ('<?xml version="1.0"?><Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">'
+       '<Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/worksheet" Target="worksheets/sheet1.xml"/>'
+       '<Relationship Id="rId2" Type="http://schemas.microsoft.com/office/2006/relationships/vbaProject" Target="vbaProject.bin"/></Relationships>')
+sheet = '<?xml version="1.0"?><worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main"><sheetData/></worksheet>'
+vba = b"\xd0\xcf\x11\xe0\xa1\xb1\x1a\xe1" + b"HELLO-VBA-PROJECT-BYTES" + bytes(range(32))
+with zipfile.ZipFile(os.path.join(tmp, "macro_demo.xlsm"), "w", zipfile.ZIP_DEFLATED) as z:
+    z.writestr("[Content_Types].xml", ct)
+    z.writestr("_rels/.rels", root)
+    z.writestr("xl/workbook.xml", wb)
+    z.writestr("xl/_rels/workbook.xml.rels", rel)
+    z.writestr("xl/worksheets/sheet1.xml", sheet)
+    z.writestr("xl/vbaProject.bin", vba)
+open(os.path.join(tmp, "vba_expected.bin"), "wb").write(vba)
+print("built", os.path.join(tmp, "macro_demo.xlsm"))
+PY
+
+# 2. Round-trip through the engine.
+echo "--- view.macros on the input (what the app sees) ---"
+"$CLI" run --in "$NATIVE_TMP/macro_demo.xlsm" --cmd 'view.macros={}' | tail -1
+"$CLI" run --in "$NATIVE_TMP/macro_demo.xlsm" --cmd "file.save={\"path\":\"$JSON_TMP/macro_out.xlsm\"}" | tail -1
+
+# 3. Assert the blob survived byte-identical with correct package wiring.
+"$PYTHON" - "$NATIVE_TMP" <<'PY'
+import zipfile, os, sys
+tmp = sys.argv[1]
+exp = open(os.path.join(tmp, "vba_expected.bin"), "rb").read()
+with zipfile.ZipFile(os.path.join(tmp, "macro_out.xlsm")) as z:
+    got = z.read("xl/vbaProject.bin")
+    ct = z.read("[Content_Types].xml").decode()
+    rels = z.read("xl/_rels/workbook.xml.rels").decode()
+ok = (got == exp
+      and "macroEnabled.main+xml" in ct
+      and "/xl/vbaProject.bin" in ct
+      and "relationships/vbaProject" in rels)
+print("blob byte-identical:", got == exp)
+print("macro-enabled main content type:", "macroEnabled.main+xml" in ct)
+print("vbaProject content-type override:", "/xl/vbaProject.bin" in ct)
+print("vbaProject relationship:", "relationships/vbaProject" in rels)
+sys.exit(0 if ok else 1)
+PY
+
+echo "PASS: the VBA project survived the round-trip."