Fix: Link selection and editing

[AtlasAutocode]

Description

Fix assertion when link text shortened in dialog and text of link had been selected.
Prevent link attribute extending over new line.
collectStyles when selection includes blank line.

Related Issues

• Fix Link editing error: "type 'Null' is not a subtype of type 'Block' in type cast" #2081

Type of Change

• ✨ New feature: Adds new functionality without breaking existing features.
• [ X ] 🛠️ Bug fix: Resolves an issue without altering current behavior.
• 🧹 Code refactor: Code restructuring that does not affect behavior.
• ❌ Breaking change: Alters existing functionality and requires updates.
• [ X ] 🧪 Tests: Adds new tests or modifies existing tests.
• 📝 Documentation: Updates or additions to documentation.
• 🗑️ Chore: Routine tasks, or maintenance.
• ✅ Build configuration change: Changes to build or deploy processes.