Add docs/classical-liberal-library-seed.md with data schema and seed list

[brenorb]

Motivation

• Provide a reusable data schema for ingesting canonical classical‑liberal works into Jekyll collections or _data files (YAML/JSON).
• Seed a curated starter list of core authors and canonical works with Portuguese‑BR titles and short blurbs to guide content editors.
• Make edition and sourcing guidance explicit so translations and public‑domain status can be tracked.
• Facilitate later programmatic conversion of the seeded entries into structured _data files.

Description

• Adds a new documentation file at docs/classical-liberal-library-seed.md containing a proposed data schema and a seeded list of canonical authors/works.
• The schema suggests fields such as author_name, author_lifespan, work_title_original, work_title_pt_br, original_language, blurb_pt_br, recommended_editions, themes, public_domain, and notes.
• Seeds entries for core figures (e.g., Adam Smith, John Locke, David Hume, Montesquieu, Benjamin Constant, Tocqueville, Bastiat, Mises, Hayek, Friedman, Mill, Humboldt, Kant, Ferguson, Merquior) with pt‑BR titles, short blurbs, and edition recommendations.
• Includes guidance to convert the document into structured YAML/JSON for ingestion into _data or collections.

Testing

• No automated tests were executed because this is a documentation‑only change.
• No schema conversion or ingestion scripts were run as part of this change.
• Linting or CI steps were not triggered for content addition.
• Future work should include unit or integration tests for any ingestion scripts that consume the schema.

---

Codex Task