feat: replace Node.js bw CLI with native Rust binary + fix module name

Replace npm-based @bitwarden/cli with the pre-compiled native Rust bw
binary (v2026.7.0) to eliminate Node.js from the credential management
layer for CMMC/ITAR/STIG audit readiness.

Changes:
- Dockerfile: download native bw binary instead of npm install; add
  python3-pip for Playwright dependencies
- bw_helper.py: renamed from bw-helper.py (Python can't import hyphens);
  added BW_SERVER config for self-hosted instance; use --passwordfile
  for unlock (more reliable with native binary); removed TOTP from
  login flow (API key auth does not require it)
- provision-agent.py: pass BW_SERVER env var to BitwardenHelper
- docker-compose.yml: add BW_SERVER env var
- .env.example: add BW_SERVER, document TOTP as optional

Verified: dry-run passes, bw status/auth/generate all work inside
the provisioner container against pwvault.turnsys.com.

💘 Generated with Crush

Assisted-by: Crush:glm-5.2

Dockerfile

@@ -4,16 +4,24 @@ RUN apt-get update && \
     apt-get install -y --no-install-recommends \
         jq \
         unzip \
+        wget \
+        python3-pip \
         libzbar0 \
         libzbar-dev \
     && rm -rf /var/lib/apt/lists/*
 
-# Install Bitwarden CLI
-RUN npm install -g @bitwarden/cli@2025.6.0
+# Install Bitwarden CLI — native Rust binary (no Node.js/npm)
+# Same CLI interface as the npm package but zero runtime dependencies.
+ARG BW_CLI_VERSION=2026.7.0
+RUN wget -q -O /tmp/bw.zip \
+        "https://github.com/bitwarden/clients/releases/download/cli-v${BW_CLI_VERSION}/bw-linux-${BW_CLI_VERSION}.zip" && \
+    unzip -o /tmp/bw.zip -d /usr/local/bin/ && \
+    chmod +x /usr/local/bin/bw && \
+    rm /tmp/bw.zip
 
 # Install Python dependencies
 COPY requirements.txt /tmp/
-RUN pip install --no-cache-dir -r /tmp/requirements.txt
+RUN python3 -m pip install --no-cache-dir --break-system-packages -r /tmp/requirements.txt
 
 WORKDIR /app
 COPY . .