Gate PeriodicMetricReader self-observability by internal telemetry version

[Debashismitra01]

What was changed

• Added support for configuring PeriodicMetricReader with an InternalTelemetryVersion.
• Updated MetricExporterConfiguration to propagate the configured telemetry version when creating PeriodicMetricReader.
• Gated metric reader self-observability initialization based on the configured telemetry version.
• Preserved existing SDK behavior by defaulting PeriodicMetricReaderBuilder to InternalTelemetryVersion.LATEST.

Why?

PeriodicMetricReader always emitted otel.sdk.metric_reader.collection.duration whenever a real MeterProvider was available, regardless of OTEL_EXPERIMENTAL_SDK_TELEMETRY_VERSION.

Tracing and logging already gate SDK self-observability using InternalTelemetryConfiguration.getVersion(config). This change aligns metric reader self-observability with the existing behavior while preserving the default behavior for direct SDK users.

Fixes #8566

[otelbot]

⚠️ API changes detected — additional maintainer review required

@jack-berg @jkwatson

This PR modifies the public API surface area of the following module(s):

• opentelemetry-sdk-metrics

Please review the changes in docs/apidiffs/current_vs_latest/ carefully before approving.

[codecov]

Codecov Report

❌ Patch coverage is 90.90909% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 91.63%. Comparing base (fef8fdb) to head (525244f).

Files with missing lines	Patch %	Lines
...metry/sdk/metrics/export/PeriodicMetricReader.java	75.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #8597      +/-   ##
============================================
+ Coverage     91.62%   91.63%   +0.01%     
- Complexity    10321    10325       +4     
============================================
  Files          1013     1013              
  Lines         27287    27295       +8     
  Branches       3203     3203              
============================================
+ Hits          25001    25012      +11     
+ Misses         1559     1558       -1     
+ Partials        727      725       -2     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.