docs: fork hygiene — README banner, upstream sync policy, fork changelog

[axisrow]

Summary

• README: fork banner at the top — actively maintained fork of matt1398/claude-devtools (upstream dormant since 2026-05), carrying session-audit CLI, Claude Code plugin, fixes
• README: new «Upstream sync policy» section — upstream fetched but not expected to move, local work lives in main + feature branches, upstream PRs (fix(parser): parse short model ids without date suffix matt1398/claude-devtools#235) closed as "carried in fork" once applied locally
• CHANGELOG.md: first fork entry — session-audit CLI (feat(cli): token analytics — session audit + sessions inventory #1); upstream entries kept unchanged

Closes #7

🤖 Generated with Claude Code

[axisrow]

Verdict: changes requested (one factual fix; otherwise accurate and well-scoped docs PR).

Verified claims: upstream dormancy holds (last commit on matt1398/claude-devtools is 2026-05-13); pnpm analyze:session / pnpm analyze:sessions exist in package.json and match PR #1; upstream PR matt1398#235 exists and is open; anchor #upstream-sync-policy matches the new heading and the relative link from CHANGELOG.md resolves; the Fork section above [Unreleased] is acceptable since it is explicitly explained.

One blocking finding inline: the README banner advertises a Claude Code plugin that does not exist in the repo. Fix that line and this is good to merge.

[axisrow]

Verdict: approved (no inline findings).

Re-review of head 36882fc after the previous round: the blocking finding is fixed — the README banner no longer advertises a Claude Code plugin (now: session-audit CLI and fixes); no plugin mentions remain in the README at this head.

All other claims were verified previously and are unchanged: upstream dormancy holds (last upstream commit 2026-05-13); pnpm analyze:session / pnpm analyze:sessions exist in package.json and match the CHANGELOG Fork entry and PR #1; upstream PR matt1398#235 exists and is open; the #upstream-sync-policy anchor and the relative CHANGELOG link resolve; the Fork section placement above [Unreleased] is explicitly explained.

Docs-only diff, nothing to test. Good to merge.