chore(release): prepare 2.0.1

[DavidBabinec]

Bumps the ten version files the release script tracks, and writes the 2.0.1
notes into both CHANGELOG.md and readme.txt.

The changelog needed the most work. [Unreleased] held only the remote import
entry, so both Bricks fixes, all three Figma fixes, and the BEM regression were
unrecorded, and readme.txt had no 2.0.1 section at all. That is the file
WordPress users actually read. Seven user-facing changes are now listed.

I applied the same replacements scripts/version-change.ts performs rather
than running it, because its prompt is an arrow-key menu and its auto-commit
message (BUMP: 2.0.1) does not match the Conventional Commits rule the
pre-commit hook enforces.

Verification

bun run test:www                      # 23 suites, 147 pass, 0 fail
check-open-source-boundaries.ts all   # passed

Version constants after the bump:

core-framework.php   CORE_FRAMEWORK_VERSION  '2.0.1'
readme.txt           Stable tag: 2.0.1
version.ts           APP_VERSION = "2.0.1"

Notes

The only remaining 2.0.0 in those files is the replace-in-files-cli
dependency range, which is correct.