This pull request introduces a production-grade, security-hardened Docker Staging environment configuration for **NexusReader**, prepared directly from the `develop` branch.
### 🚀 Key Additions
1. **`docker-compose.stage.yml`**:
- Deploys five isolated containers (`nexus-web-stage`, `nexus-db-stage`, `nexus-qdrant-stage`, `nexus-neo4j-stage`) inside a dedicated `nexus-stage` bridge network.
- Sets non-conflicting port mappings to allow staging to run concurrently with other environments on the same host (e.g., Web on `5080`, Postgres on `5438`, Neo4j HTTP on `7488`).
- Configures robust container healthchecks (`curl` for Qdrant, `wget` for Neo4j, `pg_isready` for Postgres).
- Maps dedicated named persistent volumes for databases (`pgdata_stage`, `qdrant_stage_data`, `neo4j_stage_data`) to prevent data loss.
- Maps separate persistent volumes specifically for dynamic web uploads (`stage_www_uploads` for EPUBs, `stage_www_covers` for covers) without overriding the compiled static web client files.
2. **`.env.stage.template`**:
- A clean deployment environment template providing a blueprint of all variables.
- Copied to `.env.stage` locally during deployment to inject secrets securely.
- Mandates a secure `NEXUS_ADMIN_PASSWORD` (checked by `DbInitializer` for staging/production builds).
3. **`.gitignore`**:
- Explicitly ignores local environment configurations (such as `.env.stage`) to prevent accidentally committing credentials, while keeping the `.env.stage.template` tracked.
---
### 🧪 Verification Performed
- **Docker Compose Validation**: Ran `docker compose -f docker-compose.stage.yml --env-file .env.stage config` successfully with zero configuration or parsing errors.
- **Solution Compilation**: Ran `dotnet build NexusReader.slnx --no-restore` from root — **SUCCESS** with `0` compile errors.
- **Automated Tests**: Ran `dotnet test --no-restore` — **SUCCESS** (all 20/20 unit tests passed).
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Co-authored-by: Marek Jasiński <jasins.marek@gmail.com>
Reviewed-on: #67
Co-authored-by: Antigravity <antigravity@google.com>
Co-committed-by: Antigravity <antigravity@google.com>
