DogStatsD v1.2 Container ID support with sampling support

[marc-harrison]

Fixes #640.

[Copilot]

Pull Request Overview

This PR adds support for DogStatsD v1.2 container ID extension, allowing metrics to include container ID information via a |c:<container_id> suffix. The implementation extends the existing parser to handle up to 5 components (increased from 4) and adds parsing logic for the container ID section.

• Increased component limit from 4 to 5 to accommodate the new container ID field
• Added parsing logic for the |c:<container_id> format with proper validation
• Enhanced test coverage for various container ID scenarios including sampling, different metric types, and malformed inputs

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
pkg/line/line.go	Implements container ID parsing logic and increases component limit
pkg/line/line_test.go	Adds comprehensive test cases for container ID functionality

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[pedro-stanaka]

it looks mostly good, the log line will show the wrong message, if I am not mistaken, no?

[pedro-stanaka]

Looks good. Thanks for the contribution.