[PM-33152] Fix: InvalidCastException on attachment upload as admin

[boris324]

Summary

• Fixes Unable to upload attachments due to InvalidCastException #7062
• CipherOrganizationDetails cannot be cast to CipherDetails when admin uploads attachments
• Added type check with fallback to base ReplaceAsync(Cipher) in two locations:
  • CreateAttachmentForDelayedUploadAsync (line ~236)
  • CreateAttachmentAsync (line ~290)
• Matches existing pattern already used in DeleteAttachmentAsync (line ~897)

Test plan

• Upload attachment as org admin → should succeed (was 500 error)
• Upload attachment as regular user → should still work as before
• Delete attachment as admin → should still work (unchanged)

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[bitwarden-bot]

Thank you for your contribution! We've added this to our internal tracking system for review.
ID: PM-33152
Link: https://bitwarden.atlassian.net/browse/PM-33152

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