Part 2 of PAP-68. Stop auto-assigning a project color on create so new
projects persist color = null (and icon = null) and render the neutral
gray-on-gray tile in the list and sidebar via ProjectTile.
- server: remove the auto-color palette block in projectService.create;
color now stays null unless explicitly supplied. Drop the now-unused
PROJECT_COLORS import.
- ui: NewProjectDialog no longer sends a random PROJECT_COLORS value on
create. Drop the now-unused import.
- test: assert create defaults color to null (no auto-assign) and still
persists an explicit color when supplied.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
