refactor(Core): fix few static analysis

[Grimdhex]

Changes Proposed:

This PR proposes changes to:

• Core (units, players, creatures, game systems).
• Scripts (bosses, spell scripts, creature scripts).
• Database (SAI, creatures, etc).

Details :

1. HostileReference contains two methods creating "event" but one of tree variable of ThreatRefStatusChangeEvent is not initialize
2. Fix GraveYard ID initilization and micro-optimization by moving data instead copy them.
3. In WorldSocket::ReadDataHandlerResult WorldSocket::ReadDataHandler(), we move packet into a new variable "packetToQueue" but it's recall one time later. Fix the logic by calling packetToQueue instead.

Issues Addressed:

• Closes

SOURCE:

The changes have been validated through:

• Live research (checked on live servers, e.g Classic WotLK, Retail, etc.)
• Sniffs (remember to share them with the open source community!)
• Video evidence, knowledge databases or other public sources (e.g forums, Wowhead, etc.)
• The changes promoted by this pull request come partially or entirely from another project (cherry-pick). Cherry-picks must be committed using the proper --author tag in order to be accepted, thus crediting the original authors, unless otherwise unable to be found

Tests Performed:

This PR has been:

• Tested in-game by the author.
• Tested in-game by other community members/someone else other than the author/has been live on production servers.
• This pull request requires further testing and may have edge cases to be tested.

How to Test the Changes:

• This pull request can be tested by following the reproduction steps provided in the linked issue
• This pull request requires further testing. Provide steps to test your changes. If it requires any specific setup e.g multiple players please specify it as well.

Known Issues and TODO List:

• [ ]
• [ ]

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[Grimdhex]

Tests done : GraveYard work always correctly and test with BWL bosses for ThreatRef (special case when the current victim die and when he is disconnect). Don't seems to break something.