Fix OpenTelemetry initialization - remove ENABLE_OPENTELEMETRY dependency

- Always initialize OpenTelemetry in Django settings (instrumentation always enabled)
- Remove ENABLE_OPENTELEMETRY feature flag from config.py
- Simplify views.py OpenTelemetry imports to always use real implementation
- Export control now handled by OTEL_EXPORT_ENABLED environment variable only

This ensures OpenTelemetry is properly initialized during Django startup
and the Prometheus metrics server starts correctly.

config.py

@@ -316,13 +316,6 @@ ENABLE_MALICIOUS_CONTENT_SCAN = True
 # Logging configuration - can be overridden in local config
 # Example: LOGS_DIR = "/var/log/ivatar"  # For production deployments
 
-# OpenTelemetry feature flag - can be disabled for F/LOSS deployments
-ENABLE_OPENTELEMETRY = os.environ.get("ENABLE_OPENTELEMETRY", "false").lower() in (
-    "true",
-    "1",
-    "yes",
-)
-
 # This MUST BE THE LAST!
 if os.path.isfile(os.path.join(BASE_DIR, "config_local.py")):
     from config_local import *  # noqa # flake8: noqa # NOQA # pragma: no cover