Minor performance improvements

[oschwald]

• perf: iterative nextValueOffset in DataDecoder
• perf: dual-child read + traversal tweaks

[Copilot]

Pull Request Overview

This PR implements minor performance improvements focused on reducing redundant operations in network traversal and data decoding. The changes optimize node reading by introducing a dual-child read function and replace recursive value offset calculation with an iterative approach.

• Introduces readNodePairBySize function to read both left and right child pointers in a single operation
• Replaces recursive nextValueOffset implementation with iterative approach to reduce function call overhead
• Updates network traversal code to use the new dual-child reading function

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
traverse.go	Updates NetworksWithin to use new readNodePairBySize function for reading both child pointers simultaneously
reader.go	Adds readNodePairBySize function that reads left and right child pointers in one operation with optimized bounds checking
internal/decoder/data_decoder.go	Converts recursive nextValueOffset to iterative implementation to reduce call stack overhead

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[Copilot]

[nitpick] The comment is helpful but could be more precise. Consider clarifying that we're skipping the pointer representation itself, not dereferencing the pointer to skip its target value.

Suggested change

	// To skip it, just move past the pointer bytes; do NOT follow
	// the pointer target here.
	// To skip it, just move past the pointer bytes representing the pointer itself;
	// do NOT dereference the pointer or skip the value it points to here.