docs: update CHANGELOG for harmonization pass 2

Author: t0kubetsu

CHANGELOG.md

@@ -9,6 +9,24 @@ Version numbers follow [Semantic Versioning](https://semver.org/spec/v2.0.0.html
 
 ## [Unreleased]
 
+### Added
+- `info groups` sub-command — lists all quantum-safe TLS and SSH key exchange
+  groups with their IANA codepoint and governing standard.
+- `pytest-mock>=3.12` added to dev extras.
+
+### Changed
+- `assessor.assess()`: parameters after `target` are now keyword-only
+  (enforced by `*,`); `timeout` type corrected from `int` to `float`
+  (default `10.0`), consistent with all other platform modules.
+- All `Optional[X]` type hints replaced with `X | None` (PEP 604) throughout
+  `assessor.py`, `cli.py`, `models.py`, and `tls_utils.py`.
+- `cli`: `--version` short flag changed from `-v` to `-V` (uppercase),
+  consistent with all other platform modules.
+- `reporter`: `print_report()` renamed to `print_full_report()`;
+  `print_report` is kept as a deprecated alias. `save_report()` now raises
+  `ValueError` for unsupported file extensions instead of silently falling
+  back to plain text.
+
 ---
 
 ## [0.5.1] — 2026-05-15