feat: daily vani

migrations/0044_create_vani_of_the_day.up.sql

@@ -0,0 +1,20 @@
+-- "Vāṇī of the Day" — one randomly-chosen piece of content (a prose chapter,
+-- a verse, or a transcript/lecture) surfaced on the home page each day.
+--
+-- One row per calendar day (UTC). The pick is chosen once — the first request
+-- of the day writes it and everyone sees the same item that day. `ref_id`
+-- (`<kind>:<mongo _id hex>`) identifies the underlying content so the picker
+-- can avoid repeating anything served in the last 90 days. `payload` is the
+-- prebuilt display blob (title/subtitle/href/…) so the CTA renders without
+-- re-reading Mongo.
+CREATE TABLE IF NOT EXISTS vani_of_the_day (
+    day        DATE        PRIMARY KEY,
+    kind       TEXT        NOT NULL,
+    ref_id     TEXT        NOT NULL,
+    payload    JSONB       NOT NULL,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+-- Serves the "not in the last 90 days" lookup (scan recent rows by ref_id).
+CREATE INDEX IF NOT EXISTS vani_of_the_day_ref_day_idx
+    ON vani_of_the_day (ref_id, day DESC);