# ALPHA50.9.21 — region-level Chat Mandala color allocation

## Scope
Replace whole-unit color blocks with deterministic color assignment to individual prepared colorable regions. The chat-profile palette remains the source of color character, while the allocator decides which region receives which color.

## Behavior
- Each prepared colorable region can receive an independent color.
- Repeated motifs are not forced to share a color.
- Dominant profile colors remain dominant, but regional weights are gently softened so secondary and accent colors remain visible.
- Large regions preserve dominant profile colors, while small decorative regions receive flatter palette weights and a stronger accent floor so repeated motifs can vary more.
- Regions are deterministically hash-shuffled and assigned using region-specific weighted draws with an area-aware component, spreading colors instead of forming large unit-sized monochrome blocks.
- Unit-level colors remain available as a compatibility fallback.
- Mapping version: `chat-profile-v6-region-allocated`.

## Privacy
No new message data is stored. The allocator consumes only already aggregated character and hashed n-gram profile data.

## Acceptance
- A template with many regions produces multiple region colors even when many regions belong to one logical unit.
- Equal inputs remain deterministic.
- Different n-gram profiles can change the regional color arrangement.
- Existing renderer, lifecycle, PNG and localization behavior remain intact.