Feat: tooltip enhancement

[LaansDole]

This will resolve #520

Key Changes:

• New RichTooltip.vue component with keyboard navigation, hover persistence, and smart positioning
• Centralized help content system in helpContent.js for all node types, edges, and UI actions
• Enhanced form fields with contextual help tooltips (DynamicFormField, FormGenerator)
• Improved workflow editor UX with tooltips on nodes, edges, and context menu actions
• Updated tutorial content and routing

[zxrys]

Thanks for the solid implementation here — this is a meaningful UX improvement and very close to merge-ready! Here are two small follow-ups before merge:

1. For user-defined/custom node types, the current tooltip fallback (“Help content coming soon.”) is not ideal.
   I suggest either:

• no tooltip for unknown/custom types, or
• explicitly limiting built-in help content to built-in node types only.

2. The Python node help text says: “Executes Python code in a sandboxed environment.”
   That is inaccurate for this project’s local deployment model. Python runs directly on the local environment (not sandboxed), so this wording should be updated to reflect actual behavior and avoid giving a false security impression.