feat(security): apply audited PR #6738 remediations and test hardening

- Enforce vision probe SSRF safe local host validation, SafeProbeBackend TOCTOU elimination, and session owner authorization
- Authorize session titling endpoints against registered owner configuration
- Sanitize sensitive metadata logging from agent loop debug logs
- Add async non-blocking execution for spec router tools and thinking decisions
- Harden email cache invalidation fencing and thread-safe mutation
- Add regression test suites for legacy browser authority, spec contracts, spec router request scoping, and task MCP delivery

src/jeff_decision.py

@@ -17,6 +17,7 @@ Env:
 from __future__ import annotations
 
 import logging
+import math
 import os
 from typing import Any, Dict, Optional
 
@@ -98,18 +99,18 @@ def score_value(answer: Optional[Dict[str, Any]]) -> Optional[float]:
     """Expected value (0..n-1) of a jeff ``score`` answer, or None."""
     if not isinstance(answer, dict):
         return None
-    if answer.get("type") == "score":
-        try:
-            return float(answer.get("score"))
-        except Exception:
+    try:
+        if answer.get("type") == "score":
+            value = float(answer.get("score"))
+        elif answer.get("type") == "choice":
+            probs = answer.get("probabilities") or {}
+            value = float(sum(i * float(p) for i, p in enumerate(probs.values())))
+        else:
             return None
-    if answer.get("type") == "choice":
-        probs = answer.get("probabilities") or {}
-        try:
-            return float(sum(i * float(p) for i, p in enumerate(probs.values())))
-        except Exception:
-            return None
-    return None
+    except Exception:
+        return None
+    # A malformed adapter reply must fall back like any other failure.
+    return value if math.isfinite(value) else None
 
 
 def choice_of(answer: Optional[Dict[str, Any]]) -> Optional[str]: