feat: add development-only data seeding with inventory and finance

- Add run_seed() in app/utils/seed_dev_data.py: users, clients, projects,
  tasks, time entries, expenses, comments, warehouses, stock items,
  warehouse stock, stock movements, currencies, tax rules, invoices,
  invoice items, and payments. Only runs when FLASK_ENV=development.
- Register 'flask seed' CLI command with options (users, clients,
  projects-per-client, tasks-per-project, days-back).
- Add scripts/seed-dev-data.py and docker/seed-dev-data.sh for local
  and Docker runs. Include seed scripts in image via Dockerfile chmod.
- Document in docs/development/SEED_DEV_DATA.md; update
  DATABASE_RECOVERY.md, DOCKER_COMPOSE_SETUP.md, and development README.

scripts/seed-dev-data.py

@@ -0,0 +1,74 @@
+#!/usr/bin/env python3
+"""
+Development Data Seed Script
+
+Seeds the database with test data for local development. Only runs when
+FLASK_ENV=development. Creates users, clients, projects, tasks, time entries,
+expenses, comments, inventory (warehouses, stock items, movements), and finance
+data (currencies, tax rules, invoices, payments).
+
+Usage (local):
+    Set FLASK_ENV=development, then either:
+      python scripts/seed-dev-data.py
+      flask seed
+
+Usage (Docker):
+    docker compose exec app /app/docker/seed-dev-data.sh
+
+    Or pass FLASK_ENV and use flask:
+    docker compose exec -e FLASK_ENV=development app flask seed
+
+See docs/development/SEED_DEV_DATA.md for full documentation.
+"""
+
+import os
+import sys
+
+# Force development environment for this script so seed is allowed
+os.environ.setdefault("FLASK_ENV", "development")
+
+# Add project root to path
+project_root = os.path.abspath(os.path.join(os.path.dirname(__file__), ".."))
+sys.path.insert(0, project_root)
+os.environ.setdefault("FLASK_APP", "app")
+os.chdir(project_root)
+
+
+def main():
+    if os.getenv("FLASK_ENV") != "development":
+        print("FLASK_ENV must be 'development' to run the seed script.")
+        print("Set FLASK_ENV=development and try again.")
+        sys.exit(1)
+
+    try:
+        from app import create_app
+        from app.utils.seed_dev_data import run_seed
+
+        app = create_app()
+        with app.app_context():
+            counts = run_seed(
+                extra_users=4,
+                clients_count=20,
+                projects_per_client=4,
+                tasks_per_project=12,
+                time_entries_per_task_approx=8,
+                days_back=120,
+                expense_categories=True,
+                expenses_count=50,
+                comments_count=80,
+            )
+        print("Development seed complete:")
+        for key, value in counts.items():
+            print(f"  {key}: {value}")
+    except RuntimeError as e:
+        print(f"Error: {e}")
+        sys.exit(1)
+    except Exception as e:
+        print(f"Seed failed: {e}")
+        import traceback
+        traceback.print_exc()
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()