feat: Add enhanced CSV export with comprehensive filtering options

Implement robust CSV export feature with 8 filter options:
- Date range, user (admin), client, project, task
- Billable status, entry source, tags search

Features:
- New /reports/export/form route with modern UI
- Enhanced CSV output with task and timestamp columns
- Dynamic task loading based on project selection
- Smart filename generation with filter indicators
- Permission enforcement and analytics tracking

Files modified:
- app/routes/reports.py (enhanced routes)
- app/templates/reports/index.html (updated link)
- tests/test_routes.py (added tests)

Files created:
- app/templates/reports/export_form.html
- docs/features/CSV_EXPORT_ENHANCED.md

app/config/analytics_defaults.py

@@ -17,7 +17,7 @@ DO NOT commit actual keys to this file - they are injected at build time only.
 # PostHog Configuration
 # Replaced by GitHub Actions: POSTHOG_API_KEY_PLACEHOLDER
 POSTHOG_API_KEY_DEFAULT = "%%POSTHOG_API_KEY_PLACEHOLDER%%"
-POSTHOG_HOST_DEFAULT = "https://app.posthog.com"
+POSTHOG_HOST_DEFAULT = "https://us.i.posthog.com"
 
 # Sentry Configuration
 # Replaced by GitHub Actions: SENTRY_DSN_PLACEHOLDER

check_routes.py

@@ -0,0 +1,19 @@
+#!/usr/bin/env python3
+"""Check if export routes are registered"""
+from app import create_app
+
+app = create_app()
+
+print("\n=== Export Routes ===")
+with app.app_context():
+    for rule in app.url_map.iter_rules():
+        if 'export' in str(rule):
+            print(f"✓ {rule}")
+
+print("\n✅ Routes are registered!")
+print("\nTo access the new feature:")
+print("1. Restart your Flask app: python app.py")
+print("2. Go to: http://localhost:5000/reports")
+print("3. Click on: 'Export CSV' button")
+print("4. Or visit directly: http://localhost:5000/reports/export/form")
+