Add "Not Verified" query filter

[Copilot]

Adds ability to query for unverified annotations, complementing the existing "Verified" filter.

Changes

• QueryConstraint: Added notlike field to support negated LIKE pattern matching
• NotVerifiedConstraintResult: New constraint class using notlike='%"verifier":%' to filter annotations lacking verifier field in JSON
• QueryDialog: Registered "Not Verified" in filters list
• Tests: Coverage for notlike constraint behavior and null handling

The implementation mirrors the existing "Verified" filter pattern:

# Verified filter
QueryConstraint(column="link_value", like='%"verifier":%')

# Not Verified filter  
QueryConstraint(column="link_value", notlike='%"verifier":%')

Original prompt

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This section details on the original issue you should resolve

<issue_title>not verified query</issue_title>
<issue_description>In vars-gridview we have the ability to query for 'verified' can we add a query for 'not verified?'</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes not verified query #113

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