Refactor VMStructs

[zhengyu123]

What does this PR do?:
This is the first part of efforts to eliminating/reducing dependence on jmethodID.

A significant refactoring of vmStructs.cpp/h that replaces ~60 manual if/strcmp chains in initOffsets() with a declarative, macro-driven system (DECLARE_TYPE_FILED_DO). The core design:

• Splits the monolithic initOffsets() into init_type_sizes(), init_offsets_and_addresses(), and init_constants()
• Introduces field_with_version(...) to express per-field JDK version ranges cleanly
• Adds a verify_offsets() function (debug-only) to catch incomplete initialization
• Separates pointer-typed fields into offset vs address variants for correctness
• Standardizes NULL → nullptr, adds cast_to() template with safety assertions

Also fixed memory leak and locking bug in VMStructs::NativeMethodBind()

Motivation:
Code cleanup and reduce maintenance cost.

Additional Notes:
Disable verification phase is due to CI failure with JDK25.
Not sure what are the versions of JDK25 used by CI, but I cannot reproduce the verification failure with Zulu, Temurin and JDK25u local build.

How to test the change?:

For Datadog employees:

• If this PR touches code that signs or publishes builds or packages, or handles
  credentials of any kind, I've requested a review from @DataDog/security-design-and-guidance.
• This PR doesn't touch any of that.
• JIRA: PROF-13808

Unsure? Have a question? Request a review!

[dd-octo-sts]

CI Test Results

Run: #23265404314 | Commit: 83fce9b | Duration: 11m 17s (longest job)

✅ All 32 test jobs passed

Status Overview

JDK	glibc-aarch64/debug	glibc-amd64/debug	musl-aarch64/debug	musl-amd64/debug
8	-	✅	-	-
8-ibm	-	✅	-	-
8-j9	✅	✅	-	-
8-librca	-	-	✅	✅
8-orcl	-	✅	-	-
11	-	✅	-	-
11-j9	✅	✅	-	-
11-librca	-	-	✅	✅
17	✅	✅	-	-
17-graal	✅	✅	-	-
17-j9	✅	✅	-	-
17-librca	-	-	✅	✅
21	✅	✅	-	-
21-graal	✅	✅	-	-
21-librca	-	-	✅	✅
25	✅	✅	-	-
25-graal	✅	✅	-	-
25-librca	-	-	✅	✅

Legend: ✅ passed | ❌ failed | ⚪ skipped | 🚫 cancelled

Summary: Total: 32 | Passed: 32 | Failed: 0

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Updated: 2026-03-18 20:42:24 UTC

[pr-commenter]

Integration Tests

✅ All 40 integration tests passed

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