refactor: move Docker build files to web-app directory

Moved Dockerfile, build.sh, and .dockerignore to web-app/ for better
project encapsulation. Each project now contains its own build configuration.

## Changes
- Moved Dockerfile to web-app/ and simplified paths
- Moved build.sh to web-app/
- Moved .dockerignore to web-app/
- Updated Dockerfile to work from web-app/ context (no workspace references)
- Updated documentation for new build workflow

## Build Workflow
- Build: Run from web-app/ directory (`cd web-app && ./build.sh 2.20.0`)
- Deploy: Run from repository root (`./deploy-standalone.sh 2.20.0`)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

README.md

@@ -112,21 +112,30 @@ All backups are stored in `./mongo-backup/`:
 This directory is excluded from git via `.gitignore`.
 
 # Deploying
-The deployment is done via Docker:
-* build docker image
-* deploy Docker service
 
-## Building Docker image
-Run the following command:
+The deployment is done via Docker.
+
+## Building Docker Image
+
+From the `web-app/` directory:
+
 ```bash
-build.sh
+cd web-app
+./build.sh 2.20.0
 ```
+
 The image will be stored in the local Docker instance.
 
-## Deploying Docker service
-Run the following command:
+## Deploying Docker Service
+
+From the repository root:
+
 ```bash
-deploy.sh
+# Standalone deployment
+./deploy-standalone.sh 2.20.0
+
+# Or Swarm deployment
+./deploy-swarm.sh 2.20.0
 ```
 
 # Implementation details