Add DumbMoney sports forecasting cell

DATA_PIPELINE_LINEAGE.md

@@ -29,6 +29,19 @@ Each copied observation receives an immutable provenance reference to the protec
 source database and source row. The target database can be discarded and rebuilt
 without altering the source.
 
+For point-in-time safety, a copied row's `observed_at` is the latest valid UTC
+timestamp among its source `received_at`, `result_available_at`, and `as_of`
+fields—not the first non-empty field. The content digest commits to all three raw
+timestamps, the derived knowledge time, and the derivation rule. A completed
+result therefore cannot enter a projection before the source says that result was
+available.
+
+Rows with malformed or offset-free timestamps, source timestamps later than the
+import receipt, missing final scores, or a final result-availability time before
+the logical game start are rejected. Import receipts report per-reason quarantine
+counts and a canonical digest of the rejected source-row set without modifying the
+protected database.
+
 ## Explicit exclusions
 
 The implementation does not copy or activate:
@@ -51,9 +64,26 @@ range fall back to bounded daily requests.
 Provider availability is not guaranteed, and provider terms govern use. A fetch
 failure stays visible as an ingest error and never becomes synthetic current data.
 
+## Point-in-time DumbMoney export
+
+Normalized game observations are append-only, content-addressed revisions.
+The existing `games` table remains a compatibility view of the latest revision;
+it is not the historical source of truth. Point-in-time projections select the
+latest unambiguous revision received on or before the requested cutoff. A later
+score, schedule change, or correction is retained but cannot leak into an older
+forecast.
+
+`SportsForecastEnvelopeV1` commits to the selected revision set and exports only
+candidate research. Its three fixed authority fields prevent the envelope from
+granting order or capital permissions. Source terms still govern use; the
+envelope records references and limitations but does not grant redistribution
+or model-training rights.
+
 ## Verification
 
 Automated tests create temporary source and destination databases, verify that the
 source bytes remain unchanged, exercise normalization and aliases, and inspect the
-HTTP/API projection contracts. Operationally, recheck `git status` in Dummy after
-an import and confirm it is clean.
+HTTP/API projection contracts. They also prove deterministic envelope identity,
+future-leakage rejection, contradiction and staleness handling, and append-only
+revision retention. Operationally, recheck `git status` in Dummy after an import
+and confirm it is clean.

README.md

@@ -183,10 +183,20 @@ selected teams, point-in-time history, model version, and seed.
 | `GET` | `/api/v1/leagues/{league}/teams` | Current team picker |
 | `GET` | `/api/v1/week` | Rolling current-week projection board |
 | `POST` | `/api/v1/simulations/hypothetical` | Reproducible matchup simulation |
+| `POST` | `/api/v1/exports/dumbmoney/sports-forecast` | Candidate-only point-in-time forecast envelope |
 | `POST` | `/api/v1/data/refresh` | Bounded public schedule refresh |
 
 OpenAPI is available at `/docs`.
 
+The DumbMoney export is schema
+`dumbmoney.sports-forecast-envelope.v1`. Its canonical SHA-256 identity commits
+to the exact append-only observation revisions, cutoff, model/champion version,
+seed, draw count, distributions, evidence, provenance, data-rights warnings,
+expiry, and authority invariants. It always emits `candidate_only=true`,
+`order_authority=false`, and `capital_authority=false`. It refuses future,
+stale, ambiguous, in-progress, or completed target observations and contains no
+wagering, brokerage, order, or capital interface.
+
 ## Determinism and governance
 
 ```mermaid

src/universal_sports_engine/__init__.py

@@ -8,6 +8,10 @@
     simulate_many_analytical,
     simulate_profile_analytical,
 )
+from universal_sports_engine.dumbmoney import (
+    DumbMoneyForecastExporter,
+    SportsForecastEnvelopeV1,
+)
 from universal_sports_engine.simulation import (
     counterfactual_game,
     simulate_game,
@@ -19,6 +23,8 @@
 __all__ = [
     "AdaptiveAnalyticalResult",
     "AnalyticalResult",
+    "DumbMoneyForecastExporter",
+    "SportsForecastEnvelopeV1",
     "counterfactual_game",
     "simulate_analytical",
     "simulate_ensemble_analytical",

src/universal_sports_engine/data/models.py

@@ -32,6 +32,14 @@ class GameRecord:
     payload_hash: str
 
 
+@dataclass(frozen=True, slots=True)
+class GameObservationRevision:
+    """One immutable, content-addressed revision of a game observation."""
+
+    revision_id: str
+    game: GameRecord
+
+
 @dataclass(frozen=True, slots=True)
 class TeamRecord:
     league: str