feat(forecasting): §25 six special indices (#986, 954-C)
Add special_indices.py: 6 §25 indices in one graceful advisory card —
Launch Window (deficit-peak scan across horizons), Product Void (#981
rank_segments, quick-win), Cannibalization + Competitor Strength (§9.1
competitors, degrade w/o cad_num), Artificial Demand (NEW objective_lots
mortgage-share read on encumbrance_type/bank_name — real signal, quick-win),
Cost-of-Error (overstock × ticket). Per-index try/except → unavailable on
failure, card always returns; advisory True, confidence ≤ medium. psycopg v3.
89 tests (pure + mocked-DB + @patch orchestrator).
Light1YT
cd3b376186