Intent-based init templates with legacy aliases and color-aware selection

Init templates have been renamed to intent-based identifiers that describe what a user wants to build, rather than the technology underneath, and legacy template names are kept as aliases so existing scripts keep working. The interactive template picker now renders with color-aware terminal output that respects NO_COLOR, CLICOLOR, CLICOLOR_FORCE, and tty detection, so colors turn off automatically in non-interactive or redirected sessions.