Implement MVP: Anonymous feedback submission (User Story 1)

Complete implementation of Phase 1-3 (64 tasks):
- Phase 1: Project setup with Flask, pytest, configuration
- Phase 2: Core infrastructure (auth, models, services, testing)
- Phase 3: Anonymous feedback submission with file uploads

Features:
- Anonymous feedback submission (text and/or up to 3 file attachments)
- Multi-language support (any language accepted)
- File validation (type, size) and virus scanning (ClamAV)
- Product management with active/archived status
- File-based storage with YAML metadata
- User authentication system (Flask-Login)
- CSRF protection and rate limiting
- Test coverage: 10 passing tests (contract + integration)

Security:
- No IP address logging (FR-055 compliance)
- File type whitelist and size limits (10MB max)
- Virus scanning with graceful degradation
- Filename sanitization and secure storage

Test Results:
- 8 contract tests passed
- 2 integration tests passed
- End-to-end workflow verified

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

tests/conftest.py

@@ -0,0 +1,89 @@
+"""Pytest configuration and fixtures"""
+import os
+import pytest
+import tempfile
+import shutil
+from app import create_app
+from app.models.user import User
+
+
+@pytest.fixture
+def app():
+    """Create application for testing"""
+    app = create_app('testing')
+
+    # Create temporary data directory
+    with app.app_context():
+        os.makedirs(app.config['DATA_DIR'], exist_ok=True)
+
+    yield app
+
+    # Cleanup temporary directory
+    with app.app_context():
+        if os.path.exists(app.config['DATA_DIR']):
+            shutil.rmtree(app.config['DATA_DIR'])
+
+
+@pytest.fixture
+def client(app):
+    """Create test client"""
+    return app.test_client()
+
+
+@pytest.fixture
+def runner(app):
+    """Create test CLI runner"""
+    return app.test_cli_runner()
+
+
+@pytest.fixture
+def admin_user(app):
+    """Create administrator user for testing"""
+    with app.app_context():
+        user = User.create(
+            username='admin',
+            email='admin@example.com',
+            password='admin123',
+            role='administrator'
+        )
+        yield user
+        # Cleanup
+        user.delete()
+
+
+@pytest.fixture
+def product_owner_user(app):
+    """Create product owner user for testing"""
+    with app.app_context():
+        user = User.create(
+            username='owner',
+            email='owner@example.com',
+            password='owner123',
+            role='product_owner',
+            product_ids=['prod_0001']
+        )
+        yield user
+        # Cleanup
+        user.delete()
+
+
+@pytest.fixture
+def authenticated_admin_client(client, admin_user):
+    """Create authenticated admin client"""
+    with client:
+        client.post('/auth/login', data={
+            'username': 'admin',
+            'password': 'admin123'
+        }, follow_redirects=True)
+        yield client
+
+
+@pytest.fixture
+def authenticated_owner_client(client, product_owner_user):
+    """Create authenticated product owner client"""
+    with client:
+        client.post('/auth/login', data={
+            'username': 'owner',
+            'password': 'owner123'
+        }, follow_redirects=True)
+        yield client