Add job detail template with execution history and metrics display

- Created a new job_detail.html template extending base.html
- Implemented a macro for rendering nested data structures
- Added sections for job identification, schedule & timing, status, configuration, execution history, and results
- Included a timeline for execution history with visual indicators for job status
- Displayed job metrics including total executions, success rate, and average duration
- Handled cases for displaying results or indicating absence of results based on job status

app/core/refdata.py

@@ -0,0 +1,14 @@
+"""Fake reference-data enums.
+
+The real `app.core.refdata` lives in the production repo. For this workspace
+we only need `ReconJobStatus` (consumed by `app.models.recon_job`).
+"""
+from enum import Enum
+
+
+class ReconJobStatus(str, Enum):
+    CREATED = "created"
+    RUNNING = "running"
+    COMPLETED = "completed"
+    FAILED = "failed"
+    CANCELLED = "cancelled"