refactor(scripts): reorganize scripts/ into seed/ and validate/ subfolders

Move 9 init/seed scripts into scripts/seed/ and 7 validation scripts
(+ validators/ subfolder) into scripts/validate/ to reduce clutter in
the root scripts/ directory. Update all references across Makefile,
CI/CD configs, pre-commit hooks, docs (~40 files), and Python imports.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/deployment/index.md

@@ -85,7 +85,7 @@ source .venv/bin/activate
 alembic upgrade head
 
 # Initialize production data
-python scripts/init_production.py
+python scripts/seed/init_production.py
 ```
 
 ### 3. Static Assets