Fix Shelly error fetching device triggers for sleeping devices

[thecode]

Proposed change

Currently the only sleeping devices that we add custom triggers are Shelly button where are already handled correctly for all other types we just return empty list (entity related automations will still be available). Fix also prevent trying to fetch triggers from devices which are not ready yet (e.g. offline).

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

Additional information

• This PR fixes or closes issue: fixes Unexpected error fetching device triggers #59268
• This PR is related to issue:
• Link to documentation pull request:

Checklist

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[probot-home-assistant]

Hey there @balloob, @bieniu, @chemelli74, mind taking a look at this pull request as it has been labeled with an integration (shelly) you are listed as a code owner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[chemelli74]

Great!