replace isNodeTitle property with corresponding tag and extend tag utilities

[Eddykasp]

depends on kieler/KLighD#234

[Copilot]

Pull Request Overview

This PR replaces the use of the isNodeTitle property with a corresponding semantic filter tag and extends tag utility functions to support this change. The refactoring moves away from direct property access to a more structured tag-based approach for identifying node titles.

• Replaces direct property access rendering.properties['klighd.isNodeTitle'] with findTag(rendering, 'isNodeTitle') calls
• Adds a new findTag utility function to search for semantic filter tags by ID
• Updates documentation comments to reflect the change from property to tag-based approach

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
packages/klighd-core/src/views-rendering.tsx	Updates rendering logic to use findTag instead of direct property access for isNodeTitle checks
packages/klighd-core/src/titles/title-storage.ts	Updates documentation comment to reflect change from property to tag
packages/klighd-core/src/filtering/util.ts	Adds PropertyHolder type and findTag utility function for semantic tag lookup

Comments suppressed due to low confidence (1)

packages/klighd-core/src/filtering/util.ts:125

• [nitpick] The type name 'PropertyHolder' is generic and doesn't clearly convey its purpose for semantic filtering. Consider renaming it to 'SemanticFilterElement' or 'TaggableElement' to better reflect its role in the semantic filtering system.

export type PropertyHolder = {

[Copilot]

The comment 'Type to check that properties exist' is unclear and doesn't explain the type's purpose. It should describe that this type represents objects that can hold semantic filter properties, not just any properties.

Suggested change

	* Type to check that properties exist.
	* Represents objects that hold semantic filter-related properties.
	* These properties are used to define and retrieve semantic filter rules and tags
	* for graph elements in the filtering process.

[soerendomroes]

If the copilot suggestion is valid (it seems to be) I would address it, but otherwise lgtm.