fix: plugin block matching for Gradle refactoring

[vpa1977]

Fix refactoring for gradle builds:

• change rule to accept plugin block rather than plugins token (this fixes issue when plugin definition was added after plugin.
• allow nested braces in plugin block, this fixes issue when plugin was inserted in version variable, e.g. foo.bar:foo:${foo-version}

[Copilot]

Pull request overview

This PR fixes Gradle plugin block matching in the refactoring logic to handle edge cases where plugin definitions are added after plugin. tokens and when version strings contain nested braces (e.g., ${foo-version}).

Key changes:

• Modified the ANTLR grammar to accept the plugin block rule instead of just the plugins token, and added support for nested braces within plugin blocks
• Updated the listener to match on RULE_plugin instead of PLUGINS token
• Added test coverage for the refactoring with nested braces in version strings

Reviewed changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/main/antlr/com/canonical/devpackspring/build/grammar/GradlePlugin.g4	Updated grammar rules to handle nested braces in plugin blocks and changed plugin_block definition
src/main/java/com/canonical/devpackspring/build/gradle/FindPluginListener.java	Changed rule matching from PLUGINS token to RULE_plugin
src/main/java/com/canonical/devpackspring/build/gradle/Refactoring.java	Added error listener suppression for cleaner output
src/test/java/com/canonical/devpackspring/build/gradle/RefactoringTests.java	Added test case for refactoring with nested braces in version strings
test-data/projects/gradle-kotlin/build.gradle.kts	Added test fixture with plugins.withType block
gradle.properties	Bumped version from 0.12.0 to 0.12.2

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 7 changed files in this pull request and generated 1 comment.

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 7 changed files in this pull request and generated 2 comments.

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