fix(cron): validate prompt local service refs at job creation (#378)

Shift-left: detect localhost/Ollama references in cron job prompts
at create/update time, not at runtime. Logs a warning with
actionable suggestion (set provider or base_url).

Changes:
- cron/jobs.py: Add import re, _LOCAL_SERVICE_CHECK_PATTERNS,
  _validate_job_prompt_local_refs(). Call from create_job()
  and update_job() when prompt is set.

Closes #378

cron/jobs.py

@@ -363,6 +363,45 @@ def save_jobs(jobs: List[Dict[str, Any]]):
         raise
 
 
+# Patterns that reference local services unreachable on cloud endpoints
+_LOCAL_SERVICE_CHECK_PATTERNS = [
+    re.compile(r"\b(?:check|verify)\s+(?:that\s+)?ollama\b", re.IGNORECASE),
+    re.compile(r"\bcurl\s+(?:localhost|127\.0\.0\.1)", re.IGNORECASE),
+    re.compile(r"\bpoll\s+localhost\b", re.IGNORECASE),
+    re.compile(r"\bping\s+localhost\b", re.IGNORECASE),
+    re.compile(r"localhost:\d+", re.IGNORECASE),
+    re.compile(r"127\.0\.0\.1:\d+", re.IGNORECASE),
+]
+
+
+def _validate_job_prompt_local_refs(prompt: str, base_url: Optional[str] = None) -> List[str]:
+    """Check if a cron job prompt references local services.
+
+    Returns list of warning messages (empty = no issues).
+    Warnings are advisory — jobs are NOT rejected.
+    """
+    warnings = []
+    if not prompt:
+        return warnings
+
+    refs = []
+    for pat in _LOCAL_SERVICE_CHECK_PATTERNS:
+        found = pat.findall(prompt)
+        if found:
+            refs.extend(found[:2])
+
+    if refs:
+        refs_str = ", ".join(f"'{r}'" for r in refs[:5])
+        warnings.append(
+            f"Prompt references local services ({refs_str}) which may be "
+            f"unreachable if the job runs on a cloud provider. "
+            f"Consider setting provider='ollama' or base_url='http://localhost:11434/v1'."
+        )
+
+    return warnings
+
+
+
 def create_job(
     prompt: str,
     schedule: str,
@@ -457,6 +496,11 @@ def create_job(
         "origin": origin,  # Tracks where job was created for "origin" delivery
     }
 
+    # Validate prompt for local service references (#378)
+    _warnings = _validate_job_prompt_local_refs(prompt, normalized_base_url)
+    for w in _warnings:
+        logging.getLogger("cron.jobs").warning("Job '%s': %s", job_id, w)
+
     jobs = load_jobs()
     jobs.append(job)
     save_jobs(jobs)