Rust: Speedup AccessAfterLifetime.ql

[hvitved]

Manually pushes magic context into transitive closure calculation, and replaces the recursive calculation with doubleBoundedFastTC.

Before

Pipeline standard for AccessAfterLifetimeExtensions::AccessAfterLifetime::mayEncloseOnStack/2#3cdefece#bf@61cb32j5 was evaluated in 30 iterations totaling 44856ms (delta sizes total: 241646328).
         241404616     ~1%    {2} r1 = SCAN `AccessAfterLifetimeExtensions::AccessAfterLifetime::mayEncloseOnStack/2#3cdefece#bf#prev_delta` OUTPUT In.1, In.0
        7379161442  ~1080%    {2}    | JOIN WITH `_AstNode::AstNode.getEnclosingBlock/0#5c38e65a_AstNode::AstNode.getEnclosingCallable/0#5a548913_Bloc__#join_rhs` ON FIRST 1 OUTPUT Lhs.1, Rhs.1
         333897324    ~40%    {2}    | AND NOT `AccessAfterLifetimeExtensions::AccessAfterLifetime::mayEncloseOnStack/2#3cdefece#bf#prev`(FIRST 2)
         297961888    ~24%    {2}    | JOIN WITH `project#AccessAfterLifetimeExtensions::AccessAfterLifetime::sourceValueScope/3#d065ba16#2` ON FIRST 1 OUTPUT Lhs.0, Lhs.1
                              return r1

The query started regressing with 108db75, which effectively computed the transitive closure over the entire virtual dispatch graph.

DCA is great; a 30 % reduction in total analysis time on rust.

[Copilot]

Pull request overview

This PR optimizes the AccessAfterLifetime.ql query to significantly improve performance by replacing a recursive transitive closure calculation with doubleBoundedFastTC. The optimization was motivated by a 30% reduction in total analysis time on Rust code after a previous change (PR #20966) caused performance regression by computing transitive closure over the entire virtual dispatch graph.

Key Changes

• Introduces a parameterized module pattern using a signature for dataflow candidate pairs
• Replaces recursive mayEncloseOnStack predicate with optimized transitive closure using doubleBoundedFastTC
• Refactors the logic into a DereferenceAfterLifetime module that takes a flow predicate as a parameter

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
rust/ql/src/queries/security/CWE-825/AccessAfterLifetime.ql	Updates the call to dereferenceAfterLifetime to use the new parameterized module, passing AccessAfterLifetimeFlow::flow/2 as the flow predicate
rust/ql/lib/codeql/rust/security/AccessAfterLifetimeExtensions.qll	Refactors dereferenceAfterLifetime into a parameterized module with optimized transitive closure using doubleBoundedFastTC, introduces TcNode type to unify sources, sinks, and block expressions for efficient graph traversal

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[Copilot]

The comment contains a duplicate word 'then'. The phrase should read "for example if f and g both call b, then depending on the caller..." with only one 'then'.

Suggested change

	* (for example if `f` and `g` both call `b`, then then depending on the
	* (for example if `f` and `g` both call `b`, then depending on the