fix(delombok): add sourcepath when module-info.java is present - #1754

Problem

When a source set contains module-info.java, the delombok task already sets
modulePath from the compile classpath (added in the hasModuleInfo branch).
However, the source directories are not added to sourcepath in that case.

This causes javac (invoked internally by Lombok's delombok) to emit errors for
every source file in the compilation unit:

error: file should be on source path, or on patch path for module

These errors are non-fatal — delombok still produces correct output — but they
are noisy and misleading.

Root cause

When javac processes module-info.java in module mode, it requires the module's
source root to be declared via --source-path so it can correctly associate
source files with the named module. Without it, javac cannot determine which
module the input files belong to.

The plugin already adds the annotation processor output directory to sourcepath
(line 117), but omits the actual source directories when module-info.java is
present.

Fix

Add sourceSet.getJava().getSourceDirectories() to the sourcepath in the same
hasModuleInfo branch that already configures the module path:

if (hasModuleInfo) {
    delombok.getModulePath().from(sourceSet.getCompileClasspath());
    delombok.getSourcepath().from(sourceSet.getJava().getSourceDirectories());
}