VIOLET V2a: V-TYPES domain layer + hypothesis properties + divergence reject-at-source

domain.py: refined scalar aliases (BarsHeld kills the bars_held=-106
UInt16 poison class by construction), DivergenceRow (DDL-shaped, frozen,
extra=forbid), ExecDriverSettings (env boundary for the V2 driver; ttl
override exists because the shared router clamps TTLs >= 0.5s),
ExecGateReport schema, beartype 'typed' decorator with
DOLPHIN_VIOLET_BEARTYPE=0 kill-switch.

divergence.py: rows now parse through DivergenceRow before the sink —
malformed rows die at the source with a rate-limited WARNING + counter,
never at the head of the CH spool.

Properties (hypothesis, derandomized): ExecutionRouter state machine
(fill/retry mutual exclusion via pop-semantics, R1 exit escalation same
trade_id, bounded retry chains, <=1 working ENTER), LatencyHistogram
percentile laws (member-of-samples, monotone, extremes), DivergenceRow
parse laws. 34 new tests; violet suite 64 green; router 77 green; zero
shared-file edits.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

prod/clean_arch/violet/divergence.py

@@ -25,7 +25,10 @@ import time
 from dataclasses import dataclass
 from typing import Any, Callable, Dict, List, Optional
 
+from pydantic import ValidationError
+
 from .clock import PlaneClock, mono_ns
+from .domain import DivergenceRow
 
 LOGGER = logging.getLogger("violet.divergence")
 
@@ -84,6 +87,7 @@ class FeedDivergenceMonitor:
         self._stream_task: Optional[asyncio.Task] = None
         self._rest_task: Optional[asyncio.Task] = None
         self.rows_emitted = 0
+        self.rows_rejected = 0
 
     # ── venue side ───────────────────────────────────────────────────────────
 
@@ -204,17 +208,29 @@ class FeedDivergenceMonitor:
             if (now - vm.mono) > self.venue_clock.staleness_budget_ns:
                 continue
             divergence_bps = (vm.mid - scan_price) / scan_price * 1e4
-            self.sink(self.table, {
-                "ts": int(time.time() * 1000),          # DateTime64(3)
-                "session_id": self.session_id,
-                "asset": key,
-                "scan_price": scan_price,
-                "venue_mid": vm.mid,
-                "divergence_bps": divergence_bps,
-                "scan_seq": int(scan_seq),
-                "venue_seq": int(vm.seq),
-                "mono_ns": int(now),
-            })
+            # V-TYPES: parse, don't validate — a malformed row dies here,
+            # never at the head of the CH spool (the bars_held lesson).
+            try:
+                row = DivergenceRow(
+                    ts=int(time.time() * 1000),          # DateTime64(3)
+                    session_id=self.session_id,
+                    asset=key,
+                    scan_price=scan_price,
+                    venue_mid=vm.mid,
+                    divergence_bps=divergence_bps,
+                    scan_seq=int(scan_seq),
+                    venue_seq=int(vm.seq),
+                    mono_ns=int(now),
+                )
+            except ValidationError as exc:
+                self.rows_rejected += 1
+                if self.rows_rejected == 1 or self.rows_rejected % 1000 == 0:
+                    self.logger.warning(
+                        "divergence row REJECTED at source (#%d) asset=%s: %s",
+                        self.rows_rejected, key, exc,
+                    )
+                continue
+            self.sink(self.table, row.model_dump())
             emitted += 1
         self.rows_emitted += emitted
         return emitted