Reduce transient allocations in hot compiler passes

[Frotty]

Summary

• bump abstractsyntaxgen from 623da1c60f to 2b3d742e8a on both the compiler and AST-generation classpaths
• replace allocation-producing iterator, stream, lambda, and collection-copy traversals with indexed access across frequently repeated IM passes
• avoid materializing combined function collections when flattening, merging locals, analyzing local-player context, and tracing Lua reachability
• preserve the required iterator for the HashMultimap removal view, where indexed traversal is not available and taking a snapshot would allocate more

Affected compiler paths

• IM flattening and helper traversal
• local-variable liveness and merging
• local-player dependency analysis
• Lua dispatch preparation
• Lua garbage collection and generic-static initializer cleanup

Motivation

These passes repeatedly traverse generated AST/IM list types across the whole program. Using their indexed access directly removes avoidable transient iterators, streams, snapshots, and aggregate sets without changing traversal order or compiler semantics.

Validation

• Gradle build and test CI passed
• published test results passed
• Codex reviewed head 51456777b3 and reported no major issues

No source-language or backend behavior change is intended.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-03T07:11:46.416547Z	5145677	Manual request

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[Frotty]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Chef's kiss.

Reviewed commit: 51456777b3

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