Add withPosition() factory method to FileSource

[lslonina]

• Refactor creation to avoid redundant canonicalization calls
• Introduced internal factory methods for clearer construction paths

Overview

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Definition of Done

• There are no TODOs left in the code
• Method preconditions are checked and documented in the method's Javadoc
• Coding conventions (e.g. for logging) have been followed
• Change is covered by automated tests including corner cases, errors, and exception handling
• Public API has Javadoc and @API annotations
• Change is documented in the User Guide and Release Notes

[mpkorstanje]

I'm not sure why my review got posted twice. I've hidden one, but now they're both hidden. 😕

[ALUMINIS650]

how to add?

[lslonina]

@mpkorstanje Thanks for the feedback — the code can definitely be simplified, especially with the instance method approach. Let’s see how the discussion on this topic evolves; I’ll keep this marked as a draft for now.

[mpkorstanje]

Suggested change

	Preconditions.notNull(filePosition, "position must not be null");
	Preconditions.notNull(filePosition, "filePosition must not be null");