fix: improve error handling for discarded hooks in WaitExecHookHandler

[priyansh17]

Signed-off-by: Priyansh Choudhary im1706@gmail.com

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Please add a summary of your change

The early-return in HandleHooks (when byContainer empty or pod==nil) should Record(... hookFailed=true ...) in the multiHookTracker, or else never Add such hooks in the first place. Otherwise, tracker cannot complete, and the restore gets stuck forever.

Does your change fix a particular issue?

Yes
Fixes #(issue)
#9749

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[codecov]

Codecov Report

❌ Patch coverage is 19.04762% with 17 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
internal/hook/wait_exec_hook_handler.go	10.52%	17 Missing ⚠️

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[priyansh17]

The suggested fix adds an error along with the warning logger so it moves the Restore to PartiallyFailed Instead of Success with warnings logged.
Let me know if you think we should ignore and just add logger warnings.

[blackpiglet]

The suggested fix adds an error along with the warning logger so it moves the Restore to PartiallyFailed Instead of Success with warnings logged. Let me know if you think we should ignore and just add logger warnings.

I think the behavior of this PR is correct.
However, it seems don't add the hook at first should be better.
Is it possible to not track the unexpected exec wait hook, and also mark the restore as PartiallyFailed?