Improve KnowledgeGraph Initialization, Namespace Handling, and Multi-Instance Support

[gesinn-it-gea]

1. Lazy initialization of KnowledgeGraphOptions
   Options pages are now created lazily via onBeforePageDisplay. This avoids generating configuration pages when a graph is not used.

2. Improved node labeling with namespaces
   Node labels correctly include namespaces, resulting in clearer and more accurate graph visualizations.

3. Isolated, independent graph instances
   Refactored JavaScript so that multiple KnowledgeGraph instances on the same page operate fully independently (own data, title, legend, event handling).

4. Legend consistency fixes
   Legend actions and IDs are now instance-scoped. removeLegendEntry was rewritten using vanilla JS to avoid collisions between multiple graphs.

5. Namespace selection in the designer
   Added a namespace dropdown to TabPanelOneLayout, giving authors precise control over where graph configurations are stored.

6. Depth parameter improvements
   Adjusted depth handling in the Query/API logic for more predictable control of traversal depth.

7. Updated test coverage
   Updated the onBeforePageDisplay test to reflect the new lazy-initialization behavior.

8. Designer layout improvements
   The SpecialKnowledgeGraphDesigner dialog was enlarged and visually cleaned up for better usability.

Motivation

• Reduce unnecessary overhead by creating configuration pages only when needed.
• Support more advanced graph-embedding scenarios where several independent graphs appear on the same page.
• Improve clarity and precision in graph outputs (including namespace-aware labels and depth handling).
• Provide a more flexible and usable designer interface to streamline graph creation workflows.

Impact

• Existing graphs continue to work without modification.
• Lower runtime overhead on wikis with many pages but few KnowledgeGraph configurations.
• Better scalability and isolation when embedding multiple graphs on the same page.
• Improved user experience in the designer and more predictable graph generation behavior.

Fixes #34, #35 and other things mentioned above