fix(version): prevent panic on empty or invalid version string in Compare

[SatyamPandey-07]

Related Issue

Fixes #644

Changes Proposed

• operator/internal/version/version.go: Validated inputs in Compare(version1, version2 string) int using IsValid(version1) and IsValid(version2) prior to accessing slice indices version1[0] and version2[0]. If either version is empty or invalid semver, Compare now returns -2. This prevents runtime index-out-of-range panics when reconciling nodes with missing or empty version state annotations and fulfills the error contract expected by skyhook_controller.go (if comparison == -2).
• operator/internal/version/version_test.go: Added table-driven test cases verifying that Compare returns -2 when given an empty string on the left, an empty string on the right, empty strings on both sides, or invalid semver strings (e.g., "dev").

How Has This Been Tested?

• Unit tests passed: Added table entries to version_test.go verifying that Compare returns -2 for empty strings on either or both sides, as well as invalid semver inputs, alongside existing ordering test cases.
• Reconcile error path verified: Verified that operator/internal/controller/skyhook_controller.go line 1968 receives -2 on invalid/empty version annotations and properly returns a reconciliation error instead of crashing.

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings

[github-actions]

Welcome to NodeWright, @SatyamPandey-07! Thanks for your first pull request.

Before review, please ensure:

• All commits are signed off and signed: git commit -s -S (see CONTRIBUTING.md)
• Commits follow Conventional Commits
• CI checks pass (tests, lint, security scan)
• The PR description explains the why behind your changes

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[github-actions]

✅ Every non-bot commit on this pull request is now signed off and signed. Thanks!

[coderabbitai]

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ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between cdc1824 and f91a0fb.

📒 Files selected for processing (4)

• issue.md
• operator/internal/version/version.go
• operator/internal/version/version_test.go
• pr.md

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📝 Walkthrough

Walkthrough

version.Compare now validates both version strings before accessing or comparing them. It returns -2 when either string is empty or invalid. Table tests cover invalid operands, and issue and PR documentation describe the reconciliation error path.

Priority: ⬆️ High

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Bug fix

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the fix: preventing panics in version.Compare for empty or invalid version strings.
Description check	✅ Passed	The description directly explains the validation change, expected -2 result, tests, and reconciliation impact.
Linked Issues check	✅ Passed	Issue #644 requires version.Compare to validate both inputs and return -2 for empty or invalid semver values. operator/internal/version/version.go now calls IsValid for both inputs before inde…
Out of Scope Changes check	✅ Passed	The changes stay within issue #644. The production change fixes version validation. The tests verify the required comparison behavior. The issue and PR documentation describe the same panic, reconcili…

✨ Finishing Touches 💡 1

🛠️ Fix failing CI checks 💡

• Commit to this branch
• Create a new PR

🧪 Generate unit tests (beta)

• Create a new PR

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[SatyamPandey-07]

@lockwobr Hi, just bumping this PR in case it slipped through your notifications. Let me know if you need any changes or further testing!

[lockwobr]

@SatyamPandey-07 Looks like maybe you commited two files you didnt mean too. Please remove them. They are not passing a test which is making your pr red.

[SatyamPandey-07]

@lockwobr Thanks for the heads up! I have rebased the branch onto the latest main, squashed the commits into a single signed and DCO-compliant commit. The PR now only modifies operator/internal/version/version.go and operator/internal/version/version_test.go. All 29 unit tests pass.