Add support for real-time data from SimpliSafe

[bachya]

Proposed change

This PR allows HASS to respond to real-time events from the SimpliSafe cloud websocket. In this first iteration, the integration will respond to these events:

• alarm_canceled
• alarm_triggered
• armed_away
• armed_away_by_keypad
• armed_away_by_remote
• armed_home
• away_exit_delay_by_keypad
• away_exit_delay_by_remote
• disarmed_by_master_pin
• disarmed_by_remote
• home_exit_delay
• lock_error
• lock_locked
• lock_unlocked

...and will update the state of alarm_control_panel and lock entities.

This PR doesn't completely remove the reliance on the REST API, since that remains the only source for many of the alarm_control_panel attributes. Therefore, the integration will continue to poll the REST API every 30 seconds (which means I won't update the docs to say this is a push-based integration).

Marking this as a draft PR while I ask the community to help me test (I'm particularly interested in how this works for v2 systems).

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Example entry for configuration.yaml:

# Example configuration.yaml
simplisafe:
  accounts:
    username: !secret simplisafe_username
    password: !secret simplisafe_password

Additional information

• This PR fixes or closes issue: Shift SimpliSafe integration (alarm and lock) to websocket #31029
• This PR is related to issue: N/A
• Link to documentation pull request: N/A

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist
• The code has been formatted using Black (black --fast homeassistant tests)
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

If the code communicates with devices, web services, or third-party tools:

• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all.
• Untested files have been added to .coveragerc.

The integration reached or maintains the following Integration Quality Scale:

• No score or internal
• 🥈 Silver
• 🥇 Gold
• 🏆 Platinum

[bachya]

I've been running this in production for over a week straight and everything appears good; no feedback to the contrary from anyone. Going to open this up for (further) review.