Implement Entity-Based People Taxonomy to Resolve Content Attribution and Display Logic Issues

The current site architecture conflates content source types (book, magazine, reference, etc.) with entity attribution, leading to inconsistent behavior where certain quotes, excerpts, or references fail to appear on relevant person pages depending on their source classification. This task proposes introducing a dedicated “People” (or entity) taxonomy that independently tags all content by subject (e.g., Nikola Tesla, Plato, Willy Wonka), allowing pages for individuals to aggregate all related content regardless of source type. This will immediately resolve display gaps through tagging while preserving existing CPT and source logic. In the long term, this creates a cleaner separation between content type, source metadata, and semantic relationships, enabling more scalable and consistent content retrieval across the site.