Skill: Remove Platform Version Support

You are tasked with removing support for an older IntelliJ Platform or Android Studio version (e.g., dropping support for 2025.1 / build 251 and raising the lower bound to 2025.2 / build 252).

Objective

Systematically update compatibility ranges, clean up CI verification loops and baseline files, identify and remove obsolete compatibility code or TODOs, check repository issues, and update documentation.

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Workflow Instructions

1. Establish Baseline & Identify Target Version

• Identify the build number being removed (e.g., 251 for 2025.1) and the new lower bound (e.g., 252 for 2025.2).
• Run ./gradlew testClasses to ensure the project compiles before making changes.

2. Update Compatibility Lower Bound (gradle.properties)

• Open gradle.properties.
• Update sinceBuild=<version> to the new lower bound build number (e.g., change sinceBuild=251 to sinceBuild=252).

3. Update CI Verification Script (tool/github.sh)

• Open tool/github.sh.
• Locate the VERIFY_BOT verification loop (for version in ...; do).
• Remove the dropped version number from the list so that ./gradlew verifyPlugin is only run against active versions in the compatibility range.

4. Remove Obsolete Verifier Baseline (tool/baseline/)

• Check tool/baseline/<version>/ for the removed version directory.
• Remove the directory and baseline file (e.g., using git rm -r tool/baseline/<version>) so baseline update scripts (tool/update_baselines.sh) do not attempt to verify unsupported versions.

5. Search & Remove Obsolete Code and TODOs

• Search Codebase: Grep src/ for references to the removed build number or version string (e.g., 251, 2025.1).
• Check Version Checks: Look for version-specific branches or workarounds (such as in DartPluginVersion.java or UI compatibility shims) that check for the removed version and simplify or remove dead code paths.
• Check TODOs: Look for comments like TODO: remove when dropping support for <version> or similar workarounds that can now be cleaned up.

6. Search Repository Issues

• Search repository issues (via GitHub issue search or issue tracker) for issues related to dropping or moving off the removed version (e.g., repo:flutter/flutter-intellij <version> or platform compatibility issues).
• Check if any open issues or tracked technical debt items specify code deletions or cleanup steps upon dropping support for that version, and implement any applicable cleanups.

7. Update Changelog

• CHANGELOG.md: Under the ### Removed section, add an entry documenting the removal (e.g., - Support for platform version 2025.1.).
• Note: Do not modify docs/building.md. Its version examples are illustrative and should not be updated when removing a platform version.

8. Verify & Validate

• Run ./gradlew testClasses to verify compilation.
• Run ./gradlew test to verify unit tests pass.
• Run ./gradlew verifyPlugin to verify that plugin verification succeeds against the new compatibility range.