feat: Add date-based entry filtering rules

[Sevichecc]

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• I have tested my changes
• There are no breaking changes
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Description

Add support for filtering entries by date using block and keep rules. This allows users to filter out future entries or entries within specific date ranges. Replace the previous PR #2976.

New Features

• Add EntryDate field to entry filtering rules
• Support the following date patterns:
  • future - Block or allow entries with future dates
  • before:YYYY-MM-DD - Filter entries before a specific date
  • after:YYYY-MM-DD - Filter entries after a specific date
  • between:YYYY-MM-DD,YYYY-MM-DD - Filter entries between two dates

Example Usage

Block rules:

EntryDate=future
EntryDate=before:2024-01-01

Keep rules:

EntryDate=between:2024-01-01,2024-12-31
EntryDate=after:2024-03-01

Changes

• Add EntryDate to valid field names in validator
• Add date pattern validation
• Add date matching logic in entry processor
• Add tests for date-based filtering

Relative Issue

Fixed #2971