Cross-provider odds divergences (two-source verification)

Per (match, market, canonical book) disagreements between our two odds providers, as detected by the divergence worker. Categories: PRICE_DIFF (same line, juice differs > threshold), LINE_DIFF (different line value), MISSING_FROM_ONE (a book one provider doesn't carry), STALE (one feed lagging). Requires an Edge plan or higher (Free / Solo / Trio receive 403). Provide match_id, or else date_from + date_to to bound the kickoff window. Response: { data: [{ match_id, sport_type, league, kickoff_utc, market, canonical_id, book_display_name, category, secondary_categories, magnitude, detected_at }], meta: { total, limit, offset, categories_present, generated_at } }. magnitude is category-specific (price_diff_pct for PRICE_DIFF, line_diff for LINE_DIFF, else null) and is an ABSOLUTE difference; it carries no direction and cannot be used to reconstruct either provider's line. The per-provider line and price values are deliberately not returned: the product here is the computed disagreement, not the upstream feeds. Returns 503 while the divergence worker is still provisioning (its table not yet created).