feat: add option to filter out future-dated entries

[Sevichecc]

Description:

This PR implements a new feature that allows users to filter out entries with future publication dates, addressing the issue raised in #2971.

Changes:

• Added a new setting "Filter future entries" in the settings page
• When enabled, this filter affects all UI pages displaying entries, except for:
  • Starred entries page
  • History page
• Added a new search query parameter without_future=true to the API for filtering future entries

For testing:
You can use this RSS feed containing future-dated entries for testing: https://hugooo.vercel.app/index.xml

Fixes #2971

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[fguillot]

What about adding a new block rule based on the entry date to filter out articles instead of making all these modifications in the web UI? With the current proposal, future articles will remain visible for people using third-party applications like GReader or Fever API.

[Sevichecc]

@fguillot Thank you for the suggestion! You're absolutely right - implementing this as a block rule would be a much better approach. Since the current block rule system doesn't support date-based filtering. I could open another PR to implement this new block rule type for future-dated entries if you think that would be a better solution.