Use prometheus/common.expfmt.NewTextParser

[aknuds1]

Upgrade to latest prometheus/common:

• Use the new prometheus/common.expfmt.NewTextParser function for instantiating expfmt.TextParsers, with the now mandatory name validation scheme. Creating TextParsers directly leads to them having an invalid name validation scheme, so it shouldn't be done.
• Use explicit metric/label name validation schemes, because the implicit variants are deprecated

[Copilot]

Pull Request Overview

This PR updates the codebase to use the new prometheus/common.expfmt.NewTextParser constructor function instead of directly instantiating expfmt.TextParser structs, adding the required UTF8 validation scheme parameter.

• Replace direct expfmt.TextParser instantiation with expfmt.NewTextParser(model.UTF8Validation) calls
• Add required import for prometheus/common/model package
• Update dependencies to support the new API

Reviewed Changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated no comments.

File	Description
prometheus/testutil/testutil.go	Replace zero-value TextParser with NewTextParser constructor
prometheus/examples_test.go	Replace zero-value TextParser with NewTextParser constructor and add model import
go.mod	Update prometheus/common dependency to version supporting new API

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[Copilot]

Pull Request Overview

This PR upgrades to the latest prometheus/common library and addresses deprecation warnings by migrating to the new explicit API patterns. The changes modernize the codebase to use the latest prometheus library standards while maintaining functionality.

• Replace deprecated implicit validation schemes with explicit validation schemes
• Use the new NewTextParser function instead of direct TextParser instantiation
• Update dependency versions to latest prometheus/common

Reviewed Changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
prometheus/testutil/testutil.go	Updates TextParser instantiation to use NewTextParser with UTF8Validation
prometheus/push/push.go	Replaces deprecated LabelName.IsValid() with explicit NameValidationScheme
prometheus/labels.go	Migrates from deprecated LabelName.IsValid() to explicit validation scheme
prometheus/internal/go_runtime_metrics.go	Updates legacy metric name validation to use explicit LegacyValidation scheme
prometheus/examples_test.go	Adds model import and uses NewTextParser with UTF8Validation
prometheus/desc.go	Replaces deprecated IsValidMetricName with explicit NameValidationScheme
go.mod	Updates prometheus/common and related dependencies to latest versions

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[vesari]

LGTM