Allow a default "all on" for enabling the API communications.

**Describe the problem you have/What new integration you would like**

When I add a new device, I sometimes forget the extra step of enabling API service calls. I appreciate the added security, but let me make that decision. I want all of my ESP devices to be enables over the api.

Surely it wouldn't take much to change my preferences with a flag.

**Please describe your use case for this integration and alternatives you've tried:**

**Additional context**

No source files, tests, or entry points are identified. Start by locating ESPHome's API configuration and device-creation flow, then determine where a user preference could control API service calls for ESP devices. Done means the requested default-all-enabled behavior is defined, implemented, and covered by tests or documented verification.

Written by the indexing model from the issue text.