[ci skip] Flatten module wrappers into stack roots

Remove the module "xxx" { source = "./module" } indirection layer
from all 66 service stacks. Resources are now defined directly in
each stack's main.tf instead of through a wrapper module.

- Merge module/main.tf contents into stack main.tf
- Apply variable replacements (var.tier -> local.tiers.X, renamed vars)
- Fix shared module paths (one fewer ../ at each level)
- Move extra files/dirs (factory/, chart_values, subdirs) to stack root
- Update state files to strip module.<name>. prefix
- Update CLAUDE.md to reflect flat structure

Verified: terragrunt plan shows 0 add, 0 destroy across all stacks.

stacks/ytdlp/yt-highlights/Dockerfile

@@ -0,0 +1,38 @@
+FROM nvidia/cuda:12.6.3-cudnn-runtime-ubuntu22.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+ENV PYTHONUNBUFFERED=1
+ENV PATH="/root/.local/bin:$PATH"
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y \
+    python3 \
+    python3-pip \
+    python3-venv \
+    ffmpeg \
+    git \
+    curl \
+    && rm -rf /var/lib/apt/lists/*
+
+# Create app directory
+WORKDIR /app
+
+# Install Python dependencies
+COPY requirements.txt .
+RUN pip3 install --no-cache-dir -r requirements.txt
+
+# Copy application code
+COPY app/ ./app/
+
+# Create data directories
+RUN mkdir -p /data/audio /data/transcripts /data/highlights /data/config /data/state
+
+# Expose port
+EXPOSE 8000
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=10s --start-period=60s --retries=3 \
+    CMD curl -f http://localhost:8000/health || exit 1
+
+# Run the application
+CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "8000"]