Add source-linked inspiration ledger

[sarthakagrawal927]

Purpose

Give visible, specific credit to the tools and ideas that shaped CodeVetter. The owner selected the Reference Ledger design and asked for an exhaustive, detailed series derived from project discussions.

What changed

• Added /inspiration with search and area filters, plus 38 static notes at /inspiration/<slug>.
• Each note names the admired work, the principle we took from it, CodeVetter's implementation boundary, an official source, and the relevant project research record.
• Distinguished shipped integrations from design and research references. The copy avoids affiliation, endorsement, feature-parity, pricing, and unsupported comparative claims.
• Added the routes to the footer, sitemap, Markdown exports, /api/ai, and agent indexes. No production dependency or server endpoint was added.

Verification

• pnpm build:landing: passed, including docs merge and internal-link validation.
• node apps/landing-page-astro/scripts/verify-agent-surfaces.mjs: 871/871 sitemap routes have Markdown and API catalog entries; privacy parity passed.
• pnpm lint, pnpm knip:strict, pnpm quality:cycles, pnpm quality:change-size, and node scripts/check-docs.mjs: passed.
• All 38 built HTML and Markdown notes contain the three article sections and source rail. External links were checked; an unavailable Panto deep link was replaced with its reachable official site.
• Foreground browser automation was not run on the operator's Mac, per repository instructions. Review the hosted site after deployment at desktop and mobile widths.

Tracks #337. Close the issue after deployment and live smoke.