JS: Hoist function declarations to the top of a block statement

[asgerf]

Fixes the issue reported in #18652

We did not hoist function declarations inside block statements, as this is not standard behaviour, but it is non-standard behaviour implemented by most engines.

The specification discusses this in B.3.2 Block-Level Function Declarations Web Legacy Compatibility Semantics though I must admit I haven't read the compatibility semantics in detail.

This PR changes it to hoist function declarations to the top of a block statement in all cases.

[Copilot]

PR Overview

This PR introduces block-level function declaration hoisting in JavaScript code to align with non-standard but common engine behavior, while removing the prior function-level hoisting method. It also bumps the extractor version to track the extractor changes.

• Updated the JavaScript extractor version in Main.java
• Removed function-level hoisting logic for IFunction bodies and replaced it with block-level hoisting logic
• Added comments referencing non-standard engine-specific behavior

Changes

File	Description
Main.java	Updated the extractor version from 2025-01-21 to 2025-02-03.
CFGExtractor.java	Removed function-level hoisting method and introduced block-level hoisting logic.

Copilot reviewed 72 out of 72 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (1)

javascript/extractor/src/com/semmle/js/extractor/CFGExtractor.java:589

• Removing the function-level hoisting method may be a breaking change if external code relies on it. Consider providing an alternative or ensuring it's no longer needed.

-    public static List<Identifier> of(IFunction fn) { ... }

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