fix: update to only render crosswalk polygons

[ktro2828]

What

This pull request updates the render_lanelets function in t4_devkit/viewer/lanelet.py to only render lanelets of subtype "crosswalk", simplifying both the filtering logic and rendering behavior. The changes remove support for rendering other lanelet subtypes, such as "road" and "shoulder".

Currently, some part of polygon meshes are lacked, and crosswalk polygons are overlapped by road lanelets.

before:

After:

Rendering logic simplification:

• The function now filters lanelets to only those with subtype equal to "crosswalk", and skips all others during rendering.
• The color and element type assignment logic is simplified to always use the "crosswalk" values, removing conditional handling for "road" and "shoulder" subtypes.

[Copilot]

Pull Request Overview

This pull request modifies the render_lanelets function to exclusively render crosswalk lanelets, addressing visualization issues where crosswalk polygons were being overlapped by road lanelets. The change simplifies the rendering logic by filtering out all non-crosswalk lanelet subtypes at the entry point and removing conditional color/element type assignments.

• Adds filtering to only process lanelets with subtype "crosswalk"
• Removes conditional logic for different lanelet subtypes ("road", "shoulder")
• Updates function documentation to clarify the crosswalk-only behavior

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[github-actions]

☂️ Python Coverage

current status: ❌

Overall Coverage

Lines	Covered	Coverage	Threshold	Status
2642	2000	76%	50%	🟢

New Files

No new covered files...

Modified Files

File	Coverage	Status
t4_devkit/viewer/lanelet.py	45%	🔴
TOTAL	45%	🔴

updated for commit: 439370d by action🐍