RR1/RR6: evidence graph and reading/media timeline

Implement RR1 and RR6 from docs/moon/roadmaps/research_derived_interactions.md.

Deliver source/citation cards, an accessible argument graph, and a filterable anime/film/TV/technical-history timeline with list fallback, provenance, licensing, deep links, and tests.

References: docs/moon/research/Interactive Features and Visual Storytelling Research.md
Roadmap IDs: RR1, RR6