VIOLET V3e-wire: launcher shadow-decision path (default OFF) + DDL applied

launch_dolphin_violet.py: _build_shadow() behind DOLPHIN_VIOLET_DECISION_SHADOW=1
(default OFF -> _build_shadow returns None, zero behavior change, verified).
Divergence driver optionally feeds VioletDecisionEngine + journals to
dolphin_violet.violet_decisions (NO orders). Self-disables if the table is
absent (no CH doom-loop, the 2026-06-11 spool lesson). 22_violet_decisions.sql
applied to CH (table present, empty). vel_div sourced from scan_payload['vel_div']
(matches pink_direct). Restart for the DARK soak held for operator.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

prod/launch_dolphin_violet.py

@@ -221,8 +221,13 @@ def _build_divergence(sink=None):
     )
 
 
-async def _divergence_driver(divergence, data_feed, poll_s: float) -> None:
-    """Shared scan-sampling loop for both DARK and observe modes."""
+async def _divergence_driver(divergence, data_feed, poll_s: float, shadow=None) -> None:
+    """Shared scan-sampling loop for both DARK and observe modes.
+
+    When ``shadow`` is provided (DOLPHIN_VIOLET_DECISION_SHADOW=1), each scan is
+    ALSO fed to the V3 VioletDecisionEngine and any actuated decision is journaled
+    to dolphin_violet.violet_decisions. This NEVER executes — muted shadow only.
+    """
     # The driver owns this feed instance and is its only connector; an
     # unconnected HazelcastDataFeed has features_map=None and every poll
     # raises 'NoneType' has no attribute 'get' at ERROR level (1 Hz).
@@ -252,6 +257,22 @@ async def _divergence_driver(divergence, data_feed, poll_s: float) -> None:
                     started = True
                 if started:
                     divergence.on_scan(snapshot)
+                if shadow is not None and started:
+                    try:
+                        sn = int(payload.get("scan_number") or 0)
+                        shadow["engine"].observe(payload, sn)
+                        vd = payload.get("vel_div")
+                        if vd is not None:
+                            now_ns = shadow["mono_ns"]()
+                            d = shadow["engine"].decide(
+                                now_ns=now_ns, scan_number=sn,
+                                capital=shadow["capital"], vel_div=float(vd),
+                                vol_ok=bool(payload.get("vol_ok", True)),
+                            )
+                            if d is not None:
+                                shadow["journal"].journal(d, mono_ns=now_ns)
+                    except Exception as exc:  # noqa: BLE001 — shadow must never die
+                        LOGGER.debug("shadow decision failed: %s", exc)
         except Exception as exc:  # noqa: BLE001 — sampling must never die
             LOGGER.debug("divergence scan sample failed: %s", exc)
         await asyncio.sleep(poll_s)
@@ -269,6 +290,52 @@ async def _dark_idle_loop(divergence_task: asyncio.Task | None) -> None:
         LOGGER.warning(msg)
 
 
+def _violet_table_present(table: str) -> bool:
+    """One-table SELECT-probe (additive tables not in REQUIRED_TABLES preflight)."""
+    ch_url = os.environ.get("CH_URL", "http://localhost:8123")
+    q = urllib.parse.quote_plus(f"SELECT 0 FROM dolphin_violet.{table} LIMIT 0")
+    req = urllib.request.Request(f"{ch_url}/?query={q}", method="POST")
+    req.add_header("X-ClickHouse-User", os.environ.get("CH_USER", "dolphin"))
+    req.add_header("X-ClickHouse-Key", os.environ.get("CH_PASS", "dolphin_ch_2026"))
+    try:
+        urllib.request.urlopen(req, timeout=5).read()
+        return True
+    except Exception:
+        return False
+
+
+def _build_shadow():
+    """V3 shadow-decision path (DOLPHIN_VIOLET_DECISION_SHADOW=1, default OFF).
+
+    Returns wiring dict or None. NEVER executes — journals muted decisions only.
+    Self-disables if violet_decisions is absent so a missing additive DDL can
+    NEVER cause a CH-flush doom-loop (the 2026-06-11 spool/disk-fill lesson).
+    """
+    if not _env_bool("DOLPHIN_VIOLET_DECISION_SHADOW", False):
+        return None
+    if not _violet_table_present("violet_decisions"):
+        LOGGER.warning(
+            "VIOLET shadow requested but dolphin_violet.violet_decisions is MISSING "
+            "— apply 22_violet_decisions.sql; shadow DISABLED (no doom-loop)."
+        )
+        return None
+    from prod.ch_writer import ch_put_violet
+    from prod.clean_arch.violet.clock import mono_ns
+    from prod.clean_arch.violet.decision_engine import VioletDecisionEngine
+    from prod.clean_arch.violet.shadow_journal import VioletDecisionJournal
+
+    sess = uuid.uuid4().hex
+    capital = float(os.environ.get("DOLPHIN_VIOLET_SHADOW_CAPITAL", "69000"))
+    # engine defaults == live BLUE base curve (max_leverage 9.0, vel_div_threshold -0.02).
+    engine = VioletDecisionEngine()
+    journal = VioletDecisionJournal(sink=ch_put_violet, session_id=sess)
+    LOGGER.warning(
+        "VIOLET DECISION SHADOW ON (session=%s ref_capital=%.0f) — journaling muted "
+        "decisions to dolphin_violet.violet_decisions; NO orders.", sess, capital,
+    )
+    return {"engine": engine, "journal": journal, "capital": capital, "mono_ns": mono_ns}
+
+
 async def run() -> None:
     _apply_violet_env()
     poll_s = float(os.environ.get("DOLPHIN_VIOLET_POLL_INTERVAL_SEC", "1.0"))
@@ -287,8 +354,9 @@ async def run() -> None:
     divergence_task = None
     if _env_bool("DOLPHIN_VIOLET_DARK_DIVERGENCE", True) or _violet_keys_present():
         divergence = _build_divergence()
+        shadow = _build_shadow()
         divergence_task = asyncio.create_task(
-            _divergence_driver(divergence, _build_data_feed(), poll_s),
+            _divergence_driver(divergence, _build_data_feed(), poll_s, shadow=shadow),
             name="violet_divergence_driver",
         )