feat: register Broca assistant evidence board

[Jammy2211]

Summary

Registers Broca's shared dashboard identity, mark and check-in heading, and documents its ownership of assistant evidence. The unhosted board is registered separately so public navigation does not point to a nonexistent Pages deployment. Adds Broca's test-suite witness and regenerates Brain's organism map from Mind.

Companion implementation: PyAutoLabs/PyAutoBroca#1. Merge this before the Broca implementation so its renderer and CI can consume the shared theme.

API Changes

Adds the broca identity to existing theme functions and the board.private_boards policy mapping. Existing public board behavior and function signatures are unchanged. See full details below.

Test Plan

• Shared theme suite passes, including private/public registration separation and contrast checks.
• Full Brain suite: 1252 passed.
• Broca consumes the real theme; browser checks pass at five widths in light/dark with copy and keyboard checks.
• Generated organism-map check passes against the paired Mind body map.

Full API Changes

Added

• broca key in board._theme.ORGANS, MARKS, _PROMPT_HEADINGS.
• board.private_boards in policy: private boards are not passed to public Pages navigation.
• test_witness.pyautobroca points to PyAutoBroca/tests.

Migration

None for existing consumers. Broca requires this registration before rendering.

Heart

YELLOW: manifest drift: workspace checkouts (manifest ↔ disk) — 1 mismatch(es) vs PyAutoMind/repos.yaml.
STALE: release validation incomplete: no rehearsal for current source.
No active freeze. Human acknowledged this exact YELLOW reason and authorized opening the PRs on 2026-10-08; merge remains human /prm.

Generated by the PyAutoLabs agent workflow.

Public visibility requested and applied on 2026-10-08 after reviewing tracked content. Raw transcripts and private project data remain excluded.