Add missing strings for Shelly voltmeter sensor

[chemelli74]

Proposed change

Add missing strings for Shelly voltmeter sensor:

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• This PR fixes or closes issue: fixes #
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[home-assistant]

Hey there @bieniu, @thecode, @bdraco, 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!

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[Copilot]

Pull request overview

This PR adds missing translation strings for Shelly voltmeter sensors that have channel names. These strings are automatically used by the configure_translation_attributes() method in the Shelly entity base class, which appends _with_channel_name to translation keys when a device has multiple channels.

Key changes:

• Adds two new translation keys for voltmeter sensors with channel name placeholders

[Copilot]

The naming pattern for these translation strings is inconsistent with the established pattern in this file. All other _with_channel_name entries place the channel name placeholder at the beginning (e.g., "{channel_name} pulse counter value", "{channel_name} power factor"), but these new entries place it at the end ("Voltmeter value {channel_name}", "Voltmeter {channel_name}").

For consistency, these should be:

• "voltmeter_value_with_channel_name": "name": "{channel_name} voltmeter value"
• "voltmeter_with_channel_name": "name": "{channel_name} voltmeter"

Suggested change

	"name": "Voltmeter value {channel_name}"
	},
	"voltmeter_with_channel_name": {
	"name": "Voltmeter {channel_name}"
	"name": "{channel_name} voltmeter value"
	},
	"voltmeter_with_channel_name": {
	"name": "{channel_name} voltmeter"