Update dependency docfx to 2.78.4

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
docfx	2.78.3 -> 2.78.4

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Release Notes

dotnet/docfx (docfx)

v2.78.4

🚀 Release Notes

🌟 New Features

• 🧩 Updated to Roslyn 4.13.0 and added .NET 10 nightly build support. (#​10577, #​10561)

🐞 Bug Fixes

• ✅ Include [Experimental] attribute support by default. (#​10566)
• ✅ Include global type metadata for all output formats. (#​10611)
• ✅ Skip non-managed assemblies to prevent runtime errors. (#​10692)
• ✅ Fix TOC grouping regression introduced by earlier refactor. (#​10700)
• ✅ Fix Bicep.js import error on the samples site. (#​10738)
• ✅ Handle IOException gracefully when file access conflicts occur. (#​10786)
• ✅ Fix PDF generation failure when navigating within the same page or hash fragment. (#​10768)
• ✅ Use textContent to correctly render header titles. (#​10790)
• ✅ Fixed nightly build CI and dependency updates. (#​10679, #​10694)
• ✅ Added event handling for AnalyzerLoadFailed to improve debugging. (#​10617)

⚡ Performance Improvements

• ⚙️ Use cached MarkdownPipeline instance to reduce re-initialization overhead. (#​10568)
• ⚙️ Reuse YamlDeserializer instance for better memory efficiency. (#​10567)
• ⚙️ Migrated test assertions to AwesomeAssertions for faster, cleaner test runs. (#​10563)
• ⚙️ Improved analyzer diagnostics and reduced noisy suggestions. (#​10578)

📘 Documentation Updates

• 📄 Minor doc fix and .slnx inclusion. (#​10610)
• 📄 Fixed config reference documentation. (#​10683)
• 📄 Corrected PlantUML class diagram link. (#​10638)
• 📄 Updated “Tabs with ***” section formatting. (#​10699)
• 📄 Fixed minor spelling errors. (#​10723)
• 📄 Updated Bicep sample to use official Highlight.js syntax. (#​10715)
• 📄 Added DeepWiki badge and improved emoji font embedding in PDF generation. (#​10680, #​10678)
• 📄 Inputs in navigation and TOC search now auto-focus when icons are clicked. (#​10754)

🙌 Contributors

Thanks to our awesome contributors for this release:
@​filzrev, @​Lombra, @​frarees, @​ettfemnio, @​Lulalaby, @​mgarstenauer, @​anthony-c-martin, @​clicktodev, @​Copilot, and everyone who helped improve this release 💙

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