T10: Monitoring, Performance, Documentation & Environment Config — 38 tests, ruff clean, docs OK

- Extended health endpoint: DB+Redis+Storage+Worker checks with degraded status
- Prometheus metrics endpoint: admin-only, text/plain format
- Metrics: http_requests_total, db_pool_connections, arq_jobs_total
- Structured JSON logging (structlog): timestamp, level, method, path, status, duration_ms, tenant_id
- Performance: page_size max 100 enforced (422), streaming CSV export (StreamingResponse)
- Scripts: seed_perf_data.py, check_indexes.py
- Docs: admin-guide.md (Deploy, Backup, Restore, Env-Vars, Troubleshooting), api-overview.md
- README updated: prod setup, API section, env profiles, admin-guide link
- .env.example: added SECRET_KEY, STORAGE_PATH, SMTP_* vars
- 38 new tests, full regression 564/564 pass (0 failures)
- Ruff: all checks passed

scripts/seed_perf_data.py

@@ -0,0 +1,139 @@
+#!/usr/bin/env python3
+"""Seed performance test data — creates N contacts in the test database.
+
+Usage:
+    python scripts/seed_perf_data.py --count 200000
+    python scripts/seed_perf_data.py --count 5000 --tenant-id <uuid>
+
+Requires DATABASE_URL environment variable or .env file.
+"""
+
+from __future__ import annotations
+
+import argparse
+import asyncio
+import os
+import sys
+import uuid
+from datetime import UTC, datetime
+
+# Add project root to path
+sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+
+from sqlalchemy import select
+from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
+
+from app.config import get_settings
+from app.models.contact import Contact
+from app.models.tenant import Tenant
+from app.models.user import User
+
+
+async def seed_contacts(count: int, tenant_id_str: str | None = None) -> None:
+    """Seed `count` contacts into the database for performance testing."""
+    settings = get_settings()
+    engine = create_async_engine(
+        settings.database_url,
+        pool_size=settings.db_pool_size,
+        max_overflow=settings.db_max_overflow,
+    )
+    session_factory = async_sessionmaker(bind=engine, expire_on_commit=False)
+
+    async with session_factory() as session:
+        # Get or create a tenant
+        if tenant_id_str:
+            tenant_id = uuid.UUID(tenant_id_str)
+            result = await session.execute(select(Tenant).where(Tenant.id == tenant_id))
+            tenant = result.scalar_one_or_none()
+            if not tenant:
+                print(f"ERROR: Tenant {tenant_id_str} not found")
+                return
+        else:
+            # Get first tenant or create one
+            result = await session.execute(select(Tenant).limit(1))
+            tenant = result.scalar_one_or_none()
+            if not tenant:
+                tenant = Tenant(name="Perf Test Tenant", slug="perf-test")
+                session.add(tenant)
+                await session.flush()
+
+        # Get or create a user for this tenant
+        result = await session.execute(
+            select(User).where(User.tenant_id == tenant.id).limit(1)
+        )
+        user = result.scalar_one_or_none()
+        if not user:
+            from app.core.auth import hash_password
+
+            user = User(
+                tenant_id=tenant.id,
+                email="perf@test.local",
+                name="Perf Test User",
+                password_hash=hash_password("TestPass123!"),
+                role="admin",
+                is_active=True,
+                preferences={},
+            )
+            session.add(user)
+            await session.flush()
+
+        tenant_id = tenant.id
+        user_id = user.id
+
+        # Seed contacts in batches
+        batch_size = 1000
+        total_seeded = 0
+        first_names = ["Hans", "Maria", "Peter", "Anna", "Klaus", "Ursula", "Werner", "Brigitte", "Jürgen", "Helga"]
+        last_names = ["Müller", "Schmidt", "Schneider", "Fischer", "Weber", "Meyer", "Wagner", "Becker", "Hoffmann", "Schäfer"]
+
+        while total_seeded < count:
+            batch = []
+            batch_count = min(batch_size, count - total_seeded)
+            for i in range(batch_count):
+                idx = total_seeded + i
+                fn = first_names[idx % len(first_names)]
+                ln = last_names[idx % len(last_names)]
+                batch.append(Contact(
+                    tenant_id=tenant_id,
+                    first_name=f"{fn}-{idx}",
+                    last_name=f"{ln}-{idx}",
+                    email=f"{fn.lower()}.{ln.lower()}-{idx}@example.com",
+                    phone=f"+49-555-{idx:06d}",
+                    created_by=user_id,
+                    updated_by=user_id,
+                ))
+            session.add_all(batch)
+            await session.commit()
+            total_seeded += batch_count
+            if total_seeded % 10000 == 0 or total_seeded == count:
+                print(f"Seeded {total_seeded}/{count} contacts...")
+
+    await engine.dispose()
+    print(f"Done: {total_seeded} contacts seeded.")
+
+
+def main():
+    """Parse arguments and run the seeding script."""
+    parser = argparse.ArgumentParser(
+        description="Seed performance test data into the LeoCRM database."
+    )
+    parser.add_argument(
+        "--count",
+        type=int,
+        default=200000,
+        help="Number of contacts to create (default: 200000)",
+    )
+    parser.add_argument(
+        "--tenant-id",
+        type=str,
+        default=None,
+        help="Tenant UUID to seed data into (default: first available tenant)",
+    )
+    args = parser.parse_args()
+
+    print(f"Starting seed: {args.count} contacts")
+    asyncio.run(seed_contacts(args.count, args.tenant_id))
+
+
+if __name__ == "__main__":
+    main()