fix: enforce type depth/size limits on PackClosure function types

[0xIcarus]

Description

PackClosure was constructing Type::Function directly, skipping the TypeBuilder depth and size checks that all other composite types go through. A deeply nested or oversized closure type could be pushed onto the operand stack unchecked.

Added TypeBuilder::create_function_ty and routed PackClosure through it. No version gate needed. Closures are already behind ENABLE_FUNCTION_VALUES

How Has This Been Tested?

• test_create_function_ty_depth: verifies depth-5 result type is rejected, depth-4 passes
• test_create_function_ty_size: verifies 5 Bool args is rejected, 4 passes (node count = max)

Key Areas to Review

Type of Change

• New feature
• Bug fix
• Breaking change
• Performance improvement
• Refactoring
• Dependency update
• Documentation update
• Tests

Which Components or Systems Does This Change Impact?

• Validator Node
• Full Node (API, Indexer, etc.)
• Move/Aptos Virtual Machine
• Aptos Framework
• Aptos CLI/SDK
• Developer Infrastructure
• Move Compiler
• Other (specify)

Checklist

• I have read and followed the CONTRIBUTING doc
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I identified and added all stakeholders and component owners affected by this change as reviewers
• I tested both happy and unhappy path of the functionality
• I have made corresponding changes to the documentation

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[blacksmith-sh]

Found 3 test failures on Blacksmith runners:

Failures

Test	View Logs
move-compiler-v2-transactional-tests::tests/compiler-v2-txn[config=baseline]::tests/ no-v1-comparison/closures/misc_1.move	View Logs
move-compiler-v2-transactional-tests::tests/compiler-v2-txn[config=no-optimize]::tests/ no-v1-comparison/closures/misc_1.move	View Logs
move-compiler-v2-transactional-tests::tests/compiler-v2-txn[config=optimize]::tests/ no-v1-comparison/closures/misc_1.move	View Logs

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