Add global search interface

[b1rger]

As a user, I want to use a global search interface to quickly find any relevant entity or relation instance.

Steps:

1. User clicks on the search icon or navigates to the search bar.
2. User enters a keyword or phrase in the search field.
3. [Nice to have] System displays suggestions or search results dynamically as the user types
4. User presses "Enter" or selects a suggestion.
5. Matching entities and relationships are displayed
6. [Nice to have] User can filter the search results

[gythaogg]

@b1rger Updated the description with an idea of what Tibschol users want - if it looks like I am hijacking your idea to do something different then I'll create a new issue and remove this description.