Initialize repository snapshot

ledger/schema/0003_shadow_receipts.sql

@@ -0,0 +1,18 @@
+-- 0003_shadow_receipts.sql
+CREATE TABLE IF NOT EXISTS shadow_receipts (
+  id TEXT PRIMARY KEY,                              -- uuid
+  ts TEXT NOT NULL DEFAULT (datetime('now')),
+  horizon_id TEXT NOT NULL,                         -- grouping key for “unrealized futures”
+  counterfactual_hash TEXT NOT NULL,                -- hash of normalized counterfactual payload
+  entropy_delta REAL,                               -- optional numeric signal (can be NULL)
+  reason_unrealized TEXT NOT NULL,                  -- short enum-like string (e.g. "blocked", "operator_abort")
+  observer_signature TEXT,                          -- optional (future: Ed25519 signature)
+  trace_id TEXT,                                    -- correlate to invocation chain
+  meta_json TEXT                                    -- redacted metadata
+);
+
+-- minimal safety constraints
+CREATE INDEX IF NOT EXISTS idx_shadow_receipts_ts ON shadow_receipts(ts);
+CREATE INDEX IF NOT EXISTS idx_shadow_receipts_horizon ON shadow_receipts(horizon_id);
+CREATE INDEX IF NOT EXISTS idx_shadow_receipts_trace ON shadow_receipts(trace_id);
+CREATE INDEX IF NOT EXISTS idx_shadow_receipts_reason ON shadow_receipts(reason_unrealized);