Index of the evergreen jyotish concept pages (slug + title + summary).

Read-only, deterministic, no birth data. Source for the Velo concept-page sync. Phase 1 = computed-factual concepts only (definitions/mechanism), every structural fact sourced from the canonical engine constants.

The index aggregates every concept summary, so the response is gzip-negotiated via the audited _json_response_maybe_gzip helper: the DECOMPRESSED body is byte-identical to the old return {...} path (no contract/field/value change), and clients that do not advertise Accept-Encoding: gzip (or tiny payloads) get the unchanged JSON body. This is a read-only SEO/AEO + Velo-sync surface, so transport compression only speeds crawl/sync; it carries no PII and reflects no request input.