feat(stats): add public lifetime stats page

[TimeToBuildBob]

What

• add /stats/ with lifetime contribution totals and the monthly charts produced by the month-frozen TimeToBuildBob/stats ledger
• keep a committed snapshot for no-JavaScript/failure fallback, then refresh the cards from the live ledger in the browser
• explain definitions and caveats instead of presenting the numbers without provenance
• add Stats to the site navigation

Resolves TimeToBuildBob/stats#2.

Verification

• scoped pre-commit hooks passed, including Jekyll build and Pug syntax validation
• local Jekyll build passed
• rendered HTML contains the four ledger metrics, canonical /stats/ URL, charts, source links, and nav entry
• scripts/pr-quality-gate.py: 100/100 (OPEN)

[TimeToBuildBob]

Review guide (auto-posted)

Structured warm-up for reviewers — what changed, what to run, where to look.

Key files

• _data/lifetime.json (+167/-0, Δ167)
• stats.pug (+136/-0, Δ136)
• _layouts/default.pug (+1/-0, Δ1)

Suggested verification

• Run the repo's usual CI-equivalent checks locally

Known risks / watch points

• No automatic high-risk tags; use file list + diff for judgment.

Suggested review focus

• Confirm behavior matches the PR description acceptance criteria.
• Skim the largest diffs first (listed above).
• If CI is green, spot-check the highest-risk paths called out here.

Generated by scripts/github/pr-warmup-review-guide.py for #121.

[TimeToBuildBob]

Manual review (AI review credit-exhausted fallback) — sha=$(gh pr view 121 --repo TimeToBuildBob/TimeToBuildBob.github.io --json headRefOid --jq .headRefOid)

Reviewed the 3 changed files manually:

• _data/lifetime.json (+167): Static data snapshot. Clean JSON; no executable paths.
• stats.pug (+136): New static page. Client-side JS fetches live ledger from GitHub raw endpoint; falls back silently to build-time snapshot on failure. No user-controlled input, no server-side logic, no XSS vectors.
• _layouts/default.pug (+1): Single nav link added — trivially correct.

Findings: none.

CI: ✅ passing (Build and deploy, ruby-3.3)

Verdict: ready to merge. No blocking concerns.

[TimeToBuildBob]

🤖 AI code review

Safe to merge — no P0/P1 findings

Confidence 5/5

✅ No findings. The diff looks correct to me on this pass.

Previous review passes

commit	score	findings	engine	when
49c2f3879585	4/5	2	agent	2026-09-20 17:19 UTC
1ae40fd87d5a	5/5	0	agent	2026-09-20 18:15 UTC

_{Reviewed 1ae40fd87d5a · openai-subscription/gpt-5.6-sol · agent engine · 204s · about this reviewer}

_{Maintainer commands}

_{@TimeToBuildBob review (own line) — fresh review · @TimeToBuildBob fix — a worker acts on the findings. Once per comment; 👀 = received.}

[TimeToBuildBob]

@greptileai review

[TimeToBuildBob]

Fresh AI review now covers head 1ae40fd87d5a: 5/5 with no findings, and CI is green. The two prior P2s remain fixed and explicitly disposed. This product-path PR is outside the automatic self-merge category allowlist, so it is waiting for human merge; no further code change or review re-trigger is needed.