GROOVY-11995 groovyc ant task could support passing through system properties or jvmargs

[paulk-asert]

This currently combines a modified GROOVY-11994 which I was using for testing. I'll split out before merging.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 82.35294% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 67.7906%. Comparing base (36870fa) to head (7b80cc5).
⚠️ Report is 9 commits behind head on master.

Files with missing lines	Patch %	Lines
...src/main/java/org/codehaus/groovy/ant/Groovyc.java	82.3529%	4 Missing and 2 partials ⚠️

Additional details and impacted files

@@                Coverage Diff                 @@
##               master      #2516        +/-   ##
==================================================
+ Coverage     67.3329%   67.7906%   +0.4576%     
+ Complexity      32276      32256        -20     
==================================================
  Files            1490       1489         -1     
  Lines          125080     123886      -1194     
  Branches        22525      22243       -282     
==================================================
- Hits            84220      83983       -237     
+ Misses          33535      32626       -909     
+ Partials         7325       7277        -48     

Files with missing lines	Coverage Δ
...src/main/java/org/codehaus/groovy/ant/Groovyc.java	50.1027% <82.3529%> (+2.4206%)	⬆️

... and 5 files with indirect coverage changes

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[testlens-app]

✅ All tests passed ✅

🏷️ Commit: 7c174dd
▶️ Tests: 97254 executed
⚪️ Checks: 24/24 completed

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[Copilot]

Pull request overview

Adds support for passing JVM arguments and system properties through the groovyc Ant task when running in fork="true" mode, aligning the task more closely with Ant’s <java> task capabilities.

Changes:

• Add nested <jvmarg>, <sysproperty>, and <syspropertyset> support for forked groovyc invocations.
• Add inheritAll to optionally pass all parent Ant project properties as -D system properties to the forked compiler JVM.
• Add tests and documentation covering the new forked JVM argument/property wiring and precedence rules.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
subprojects/groovy-ant/src/main/java/org/codehaus/groovy/ant/Groovyc.java	Implements forked JVM arg / sysproperty propagation and inheritAll behavior in the forked command line builder.
subprojects/groovy-ant/src/test/groovy/org/codehaus/groovy/ant/GroovycTest.java	Adds tests verifying JVM args, sysproperties, syspropertysets, and precedence when building the forked command line.
subprojects/groovy-ant/src/spec/doc/groovyc-ant-task.adoc	Documents new inheritAll attribute and the new nested elements for forked compiler configuration.