Grounding pipeline and recipe-search settings API (#70)

Co-authored-by: dev_agent <dev_agent@cubecraftlabs.com>

migrations/0007_recipe_grounding.sql

@@ -0,0 +1,18 @@
+-- 0007_recipe_grounding: a grounded recipe keeps what recipes.Ground
+-- returns, so a stored source_url is reused without fetching or normalizing
+-- it again: its cached photo, and normalize_recipe's method, difficulty and
+-- minutes_total (prep to table; total_minutes stays the page's own JSON-LD
+-- total). Nothing wrote recipes before Ground did, so the columns are added
+-- nullable rather than with a default no recipe has; Ground always sets
+-- photo_id, method and difficulty and refuses to reuse a row without them.
+--
+-- recipe_search_settings gains api_key_last4, the last four characters of
+-- the Brave API key, so the settings can show which key is stored without
+-- ever returning it.
+
+ALTER TABLE recipes ADD COLUMN photo_id TEXT REFERENCES photos (id);
+ALTER TABLE recipes ADD COLUMN method TEXT CHECK (method IN ('stovetop', 'oven', 'crockpot', 'grill', 'other'));
+ALTER TABLE recipes ADD COLUMN difficulty TEXT CHECK (difficulty IN ('easy', 'medium', 'hard'));
+ALTER TABLE recipes ADD COLUMN minutes_total INTEGER;
+
+ALTER TABLE recipe_search_settings ADD COLUMN api_key_last4 TEXT;