restore: re-merge ORCH-069 qg0_title_max

# Conflicts:
#	CHANGELOG.md

src/config.py

@@ -1,3 +1,4 @@
+from pydantic import field_validator
 from pydantic_settings import BaseSettings
 
 
@@ -422,6 +423,24 @@ class Settings(BaseSettings):
     tracker_live_status_ttl_s: int = 60
     tracker_live_status_timeout_s: int = 3
 
+    # ORCH-069: QG-0 upper title-length limit (entry gate _qg0_errors). The 80-char
+    # cap was a hygiene limit, not structural (slug is cut to [:30] independently,
+    # DB title TEXT is unbounded). Configurable via env ORCH_QG0_TITLE_MAX; default
+    # 200 (was hardcoded 80). Invalid/empty value -> default (graceful, no crash).
+    qg0_title_max: int = 200
+
+    @field_validator("qg0_title_max", mode="before")
+    @classmethod
+    def _qg0_title_max_default(cls, v):
+        # Graceful (ORCH-069 AC-3): empty / non-numeric env -> default 200, the
+        # process must not crash on startup. Never raises (self-hosting safety).
+        try:
+            if v is None or (isinstance(v, str) and v.strip() == ""):
+                return 200
+            return int(v)
+        except (TypeError, ValueError):
+            return 200
+
     class Config:
         env_prefix = "ORCH_"
         env_file = ".env"