Enhance crawler with seed list and SQL utilities

Add seedList module for URL initialization, comprehensive SQL utilities for database analysis, and update project configuration.

misc/sql/snapshots_date_range.sql

@@ -0,0 +1,14 @@
+-- File: snapshots_date_range.sql
+-- Shows snapshot count with date range information for each URL
+-- Usage: \i misc/sql/snapshots_date_range.sql
+
+SELECT 
+    url, 
+    COUNT(*) as snapshot_count,
+    MIN(timestamp) as first_snapshot,
+    MAX(timestamp) as last_snapshot,
+    MAX(timestamp) - MIN(timestamp) as time_span
+FROM snapshots
+GROUP BY url
+HAVING COUNT(*) > 1
+ORDER BY snapshot_count DESC;