fix: Docker-first test suite, UX improvements, and bug fixes (#100)

Dashboard UX:
- Restructure nav from 22 flat links to 6 core + MORE dropdown
- Add mobile nav section labels (Core, Intelligence, Agents, System, Commerce)
- Defer marked.js and dompurify.js loading, consolidate CDN to jsdelivr
- Optimize font weights (drop unused 300/500), bump style.css cache buster
- Remove duplicate HTMX load triggers from sidebar and health panels

Bug fixes:
- Fix Timmy showing OFFLINE by registering after swarm recovery sweep
- Fix ThinkingEngine await bug with asyncio.run_coroutine_threadsafe
- Fix chat auto-scroll by calling scrollChat() after history partial loads
- Add missing /voice/button page and /voice/command endpoint
- Fix Grok api_key="" treated as falsy falling through to env key
- Fix self_modify PROJECT_ROOT using settings.repo_root instead of __file__

Docker test infrastructure:
- Bind-mount hands/, docker/, Dockerfiles, and compose files into test container
- Add fontconfig + fonts-dejavu-core for creative/assembler TextClip tests
- Initialize minimal git repo in Dockerfile.test for GitSafety compatibility
- Fix introspection and path resolution tests for Docker /app context

All 1863 tests pass in Docker (0 failures, 77 skipped).

Co-authored-by: Alexander Payne <apayne@MM.local>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

docker/Dockerfile.test

@@ -39,7 +39,7 @@ FROM python:3.12-slim
 WORKDIR /app
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
-        curl git \
+        curl git fontconfig fonts-dejavu-core \
     && rm -rf /var/lib/apt/lists/*
 
 # Copy installed packages from builder
@@ -48,7 +48,14 @@ COPY --from=builder /usr/local/lib/python3.12/site-packages \
 COPY --from=builder /usr/local/bin /usr/local/bin
 
 # Create directories for bind mounts
-RUN mkdir -p /app/src /app/tests /app/static /app/data
+RUN mkdir -p /app/src /app/tests /app/static /app/hands /app/data /app/docker
+
+# Initialize a minimal git repo so git-dependent code (GitSafety, repo_root
+# detection) works correctly inside the container.
+RUN git config --global user.email "timmy@test" \
+    && git config --global user.name "Timmy Test" \
+    && git init /app \
+    && git -C /app commit --allow-empty -m "init"
 
 ENV PYTHONPATH=/app/src:/app/tests
 ENV PYTHONUNBUFFERED=1