feat: add automation, reminders, notifications, msg search, session export, image analysis, host exec, PWA, Docker, E2E, CI/CD

- Automation: rules CRUD (in-memory store + API)
- Reminders: CRUD (in-memory store + API)
- Notifications: push interface for future push server
- Message search: API endpoint with DB-backed query
- Session export: /sessions/:id/export → Markdown
- Image analysis: API stub for multimodal LLM
- Host exec: API stub for Docker sandbox
- PWA: manifest.json + service worker
- Docker: Dockerfile + docker-compose.yml
- E2E: Playwright test scaffold
- CI/CD: GitHub Actions workflow (go test + tsc)

backend/Dockerfile

@@ -0,0 +1,12 @@
+FROM golang:1.26-alpine AS builder
+WORKDIR /app
+COPY backend/ ./
+RUN go build -ldflags="-s -w" -o /cyrene ./cmd/cyrene/
+
+FROM alpine:3.21
+RUN apk add --no-cache ca-certificates tzdata
+COPY --from=builder /cyrene /usr/local/bin/cyrene
+COPY backend/internal/persona/ /internal/persona/
+COPY configs/persona/ /configs/persona/
+EXPOSE 8080
+CMD ["cyrene"]