Add support for Metric/Instrument tags and scopes

[wiktork]

For dotnet 8, meters now support additional information as part of the meter itself (rather than each individual value). See https://github.com/dotnet/runtime/pull/90417/files#diff-8797eae6d3e644ed047f952e10d4240fe18175f754586666823b555f46968672L1435-R1486.

This includes:

• Description
• Scope hash (may not be necessary initially since there are not many scenarios that use this)
• Tags (note this tag is not for the payload values but for the meters themselves).

The data can be gathered as part of the BeginInstrumentReporting TraceEvent. See https://github.com/dotnet/diagnostics/blob/9eee79a44914fdb703664ee6461298161339cb4f/src/Microsoft.Diagnostics.Monitoring.EventPipe/Counters/TraceEventExtensions.cs#L82.