Closes #25

changelog.md

@@ -8,6 +8,21 @@ existing Git tag; subsequent changes are listed as unreleased.
 
 ### 2026-10-20
 
+#### Added
+
+- Parse typed `BA_DEF_`, `BA_DEF_DEF_`, and `BA_` attributes with deferred
+  definitions/references, validated ranges, defaults, and explicit overrides.
+  Preserve definitions and assignments plus effective database/frame/signal values.
+- Expose optional frame format and cycle time metadata in parsed frames, runtime
+  snapshots, and tree payloads. Preserve unknown frame format labels with source
+  warnings, and report format/ID conflicts without changing ID or J1939 behavior.
+- Add attribute syntax, scope, reference, numeric, override, diagnostics, and
+  metadata propagation regressions; document supported forms and limitations.
+  Verified the qmake build, all six QtTest suites, the qmake tree target, and
+  the standalone C++17 tree test. The existing named C locale test skipped
+  because the required locale is not installed.
+
+
 #### Changed
 
 - J1939 interpretation now requires `DbcParserOptions::enableJ1939` (default off)