chore: add NilAway static analysis as pinned go tool

[analeis]

this implementation adds NilAway and was rebased onto current upstream main (NGL) to check and satisfy all NilAway cleanups and work done in advance last commit

the recommendation is to keep this tool in a minimum capacity until codebase complexity actually increases.

Reasoning:

• the tool is known for high cases and chances of false positives where the code can rather be kept cleaner for stylistic and readability reasons, and can sometimes be too conservative by design.
• It adds extra time and feedback latency between commits. Something that doesn't bother us now, but may not be something we need bogging us down in both CI and in pre-commit-hooks.

Recommended by Simon.

[analeis]

Force pushed for cleanliness

Merging the subsequent PRs #35 and #36 may still require rebase and go mod tidy.

[Vuks69]

@Simon-Weij you know more about the tool, if you approve i'll merge

[analeis]

Force pushed to rebase for dependency cleanliness since PR #36 was already merged

[analeis]

Rebased onto new upstream for maintainer ease.