Add live dashboard with SSE job events

Expose /jobs, /dedup, and /events routes backed by a new EventBus that
broadcasts job lifecycle and per-job progress over SSE. Serve a static
dashboard from front/ that lists pending and in-progress jobs, streams
agent activity, and shows completed reviews.

Also add migrate-apply/migrate-generate scripts that load .env, update
the Containerfile to ship the front assets and use the apply script, and
refresh the roadmap.

Containerfile

@@ -23,7 +23,12 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 WORKDIR /app
 COPY --from=builder /app/target/release/steep-server ./steep-server
 
+COPY front ./front
+
 COPY crates/steep-server/toasty ./toasty
 ENV MIGRATIONS_DIR=/app/toasty
 
-CMD ["sh", "-c", "./steep-server migration apply && exec ./steep-server"]
+COPY scripts/migrate-apply.sh ./scripts/migrate-apply.sh
+RUN chmod +x ./scripts/migrate-apply.sh
+
+CMD ["sh", "-c", "./scripts/migrate-apply.sh && exec ./steep-server"]