fix: compliance report iframe, findings tables, PDF fonts, delete session, orphan markers

- Compliance report iframe: removed auth requirement (UUIDs are non-guessable), fixed X-Frame-Options SAMEORIGIN on /api/
- Findings resource tables: compact HTML tables (max 4 cols, 10 rows) per non-compliant finding with affected resources from CSV
- PDF fonts: installed Liberation + DejaVu fonts in container, standardized font-family to Arial/Liberation Sans
- Delete session fix: terraform.ts used wrong URL /chat/sessions/{sid} instead of /chat/{sid}
- Chat deleteSession: read sessionId from store.getState() to avoid stale closure
- Orphan marker cleanup: startup removes stale .compliance_generating markers, status endpoint auto-expires after 10min
- Generate endpoint rejects duplicate requests while already generating
- Compliance iframe condition: only renders when ready AND not generating, prevents 404 flash
- Dockerfile: added fonts-liberation fonts-dejavu-core fontconfig packages

backend/Dockerfile

@@ -6,7 +6,7 @@ WORKDIR /app
 ARG TERRAFORM_VERSION=1.7.5
 RUN apt-get update && apt-get install -y --no-install-recommends \
     curl gcc libffi-dev unzip \
-    chromium && \
+    chromium fonts-liberation fonts-dejavu-core fontconfig && \
     ARCH=$(dpkg --print-architecture) && \
     curl -fsSL "https://releases.hashicorp.com/terraform/${TERRAFORM_VERSION}/terraform_${TERRAFORM_VERSION}_linux_${ARCH}.zip" -o /tmp/tf.zip && \
     unzip /tmp/tf.zip -d /usr/local/bin/ && rm /tmp/tf.zip && \