meta(changelog): Move plugin tracking entry to Unreleased section

Move the SENTRY_PIPELINE plugin tracking changelog entry from the
2.58.3 release section to the Unreleased section, as this feature
was merged after the 2.58.3 release.

Author: runningcode

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## Unreleased
+
+### Improvements
+
+- The `sentry-cli build upload` command now automatically tracks Sentry plugin versions from the `SENTRY_PIPELINE` environment variable ([#2994](https://github.com/getsentry/sentry-cli/pull/2994)). When `SENTRY_PIPELINE` contains a recognized Sentry plugin (e.g., `sentry-gradle-plugin/4.12.0` or `sentry-fastlane-plugin/1.2.3`), the plugin version is written to the `.sentry-cli-metadata.txt` file in uploaded build archives, enabling the backend to store metadata for size analysis and build distribution tracking.
+
 ## 2.58.4
 
 ### Fixes
@@ -13,7 +19,6 @@
 - For the `sentry-cli build upload` command, we now only auto-detect Git metadata when we detect we are running in a CI environment, unless the user manually overrides this behavior ([#2974](https://github.com/getsentry/sentry-cli/pull/2974)). This change prevents local development builds from triggiering GitHub status checks for size analysis.
   - We can detect most common CI environments based on the environment variables these set.
   - We introduced two new arguments, `--force-git-metadata` and `--no-git-metadata`, which force-enable and force-disable automatic Git data collection, respectively, overriding the default behavior.
-- The `sentry-cli build upload` command now automatically tracks Sentry plugin versions from the `SENTRY_PIPELINE` environment variable ([#2994](https://github.com/getsentry/sentry-cli/pull/2994)). When `SENTRY_PIPELINE` contains a recognized Sentry plugin (e.g., `sentry-gradle-plugin/4.12.0` or `sentry-fastlane-plugin/1.2.3`), the plugin version is written to the `.sentry-cli-metadata.txt` file in uploaded build archives, enabling the backend to store metadata for size analysis and build distribution tracking.
 - The `sentry-cli build upload` command now automatically detects the correct branch or tag reference in non-PR GitHub Actions workflows ([#2976](https://github.com/getsentry/sentry-cli/pull/2976)). Previously, `--head-ref` was only auto-detected for pull request workflows. Now it works for push, release, and other workflow types by using the `GITHUB_REF_NAME` environment variable.
 
 ### Fixes