[WF-2280] feat: Update documentation after refactoring for Angular 20 update

[tcorral]

Changes

• Fixed broken documentation links pointing to outdated app-level bundle files
• Updated all journey bundle references to correct libs/journey-bundles/ paths
• Created comprehensive guides for modern journey patterns:
  • journey-factory-patterns.md: Three-file pattern, helper wrapper functions, and composition
  • lazy-loading-guide.md: Provider scoping, troubleshooting, and best practices
• Enhanced simple-examples.md with detailed links to all journey bundles and route configurations
• Updated journeys navigation to include new documentation sections

Impact

• All documentation links now point to actual, existing files
• Developers can now learn modern journey factory patterns from customer-facing docs
• Provider scoping and lazy loading best practices are now documented
• README.md (auto-generated from .documentation) will reflect all corrections

IMPORTANT!!!

This PR cannot be merged before #596 has been merged.
This PR is documenting all the changes we have done there.