fix: upgrade Furo to 2025.12.19 to fix right panel highlight offset (#7019)

[rafaumeu]

Summary

Upgrades Furo theme from 2024.8.6 to 2025.12.19 to fix the right panel (table of contents) highlight offset issue where the active section was highlighted one index previous to the actual current section.

Root Cause

Furo's scrollspy logic for the right sidebar ("On this page") did not account for sticky/fixed elements above the main header (like custom notification banners or headers). This caused the active section detection to be off by one.

Fix

Furo PR #664 (merged in 2024.08.06) fixed this by including

in the scroll offset calculation, making the TOC highlight resilient to sticky elements above the header.

Testing

• Build docs locally and verify right panel highlights correct section
• Check for any visual regressions in the theme

Fixes #7019

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ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

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Run ID: 9f2b74d2-e6e4-4e5a-968d-12d4876fc018

📥 Commits

Reviewing files that changed from the base of the PR and between aa69671 and 719a9d9.

⛔ Files ignored due to path filters (1)

• Pipfile.lock is excluded by !**/*.lock

📒 Files selected for processing (1)

• Pipfile

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📝 Walkthrough

Walkthrough

The furo documentation theme dependency in Pipfile is updated from version ==2024.8.6 to ==2025.12.19.

Changes

Furo Dependency Update

Layer / File(s)	Summary
furo version bump Pipfile	Pins the furo Sphinx theme to ==2025.12.19, up from ==2024.8.6.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly states the Furo upgrade and the right panel highlight fix.
Description check	✅ Passed	The description matches the dependency bump and explains the intended scrollspy fix.
Linked Issues check	✅ Passed	The PR updates Furo to a newer release that aligns with the reported one-index offset issue.
Out of Scope Changes check	✅ Passed	The change is limited to a single dependency version bump with no unrelated modifications.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[esethna]

@rafaumeu there is another PR open in the repo that is meant to address this issue without upgrading the furo version: #8702

Would the changes in this PR address your concern?