chore: adopt learning-first charter and UTC run versions

tools/stamp_version.py

@@ -0,0 +1,45 @@
+#!/usr/bin/env python3
+"""Stamp a development/release run once, using its current UTC date and time.
+
+Run before building: python3 tools/stamp_version.py && make
+Ordinary rebuilds and validation retain the stamp for reproducibility.
+Historical release notes and changelog entries are deliberately not rewritten.
+"""
+from datetime import datetime, timezone
+from pathlib import Path
+import re
+
+ROOT = Path(__file__).resolve().parents[1]
+CURRENT_DOCS = (
+    "CURRENT_STATUS.md", "CLASSROOM_READINESS.md", "CLI.md", "SPEC.md",
+    "FINAL_RELEASE_CHECKLIST.md", "WEB_SERVER_PLAN.md", "GRAPHICS.md",
+    "PERFORMANCE.md", "COMPLETE_PLATFORM_ROADMAP.md", "SDL12.md",
+    "V1_16_PACKAGES_PROJECTS.md",
+)
+
+
+def main():
+    source = ROOT / "src/claro.c"
+    match = re.search(r'#define CLARO_VERSION "Claro ([^"\n]+)"', source.read_text())
+    if not match:
+        raise SystemExit("Cannot find CLARO_VERSION; no files changed")
+    previous = match.group(1)
+    version = datetime.now(timezone.utc).strftime("v%Y.%m.%d.%H%M%S")
+    paths = [source, ROOT / "README.md"]
+    paths += sorted((ROOT / "tools").glob("*.py"))
+    paths += [ROOT / "docs" / name for name in CURRENT_DOCS]
+    updates = []
+    for path in paths:
+        if path == Path(__file__).resolve() or not path.exists():
+            continue
+        old = path.read_text(encoding="utf-8")
+        new = old.replace(previous, version)
+        if new != old:
+            updates.append((path, new))
+    for path, content in updates:
+        path.write_text(content, encoding="utf-8")
+    print(f"Claro {version} (UTC); updated {len(updates)} current source/docs/validator files")
+
+
+if __name__ == "__main__":
+    main()