fix: properly instrument nested records

[oetr]

Using ClassWriter without ClassReader in asm, seems to produce
corrupted bytecode for nested records and records with annotated fields.

Prior to this fix, a segfault was triggered for nested records that
use Jazzer annotations when Jazzer was trying to access data on record
components, when trying to create a record mutator.

In addition, for non-nested records with annotated fields as for example:
record Address(byte @WithLength(max=10) [] data) {}
no suitable mutator could be found.

[Copilot]

Pull Request Overview

This PR fixes a bug in the TraceDataFlowInstrumentor that could cause segfaults when instrumenting classes with nested records, and adds a regression test to prevent this issue from recurring.

• Fixed ClassWriter initialization to pass ClassReader for proper constant pool reuse
• Added regression test for fuzzing classes with nested record types
• Configured test with Java 17 support (required for records)

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/main/java/com/code_intelligence/jazzer/instrumentor/TraceDataFlowInstrumentor.kt	Fixed ClassWriter initialization to pass ClassReader for improved compatibility with complex class structures like nested records
tests/src/test/java/com/example/NestedRecordFuzzer.java	Added regression test to verify correct instrumentation of fuzz test classes containing nested records
tests/BUILD.bazel	Added build configuration for NestedRecordFuzzer test with Java 17 support and appropriate dependencies

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[simonresch]

Very good find!
As discussed: Let's merge this and continue to reduce the ASM and/or JVM bug independently.