initial NextChair Manager.

Key additions:
* Separate platform Manager stack: [stacks/manager/compose.yaml]
* Dedicated manager authentication with signed sessions.
* Business overview dashboard.
* Add Business workflow with slug suggestions and deployment progress.
* Business detail page with start, stop, restart, update, logs, Dockge, and conservative removal actions.
* Explicit management API endpoints under [src/app/api/manager]
* Shared provisioning service layer in [provisioning.service.ts]
* CLI and UI now use the same [create-business.sh] provisioning logic.
* Registry metadata, database status, container health, and media usage reporting.
* Manager-only entrypoint mode that does not require a business database.
* Updated deployment documentation with Manager setup and Caddy routing.
Validation passed:
* Infra, Caddy, Manager, and generated business Compose configurations.
* Shell syntax checks.
* Registry generation with registry image tags.
* git diff --check.

README.md

@@ -288,6 +288,27 @@ docker compose -f stacks/infra/compose.yaml up -d
 docker compose -f stacks/caddy/compose.yaml up -d
 ```
 
+Start the Manager stack as well, after copying its environment template and
+setting a strong platform-admin password and auth secret:
+
+```bash
+cp stacks/manager/.env.example stacks/manager/.env
+docker compose -f stacks/manager/compose.yaml up -d
+```
+
+Add a Manager-only Caddy route in `stacks/caddy/sites/manager.caddy`, replacing
+the example hostname with the private/admin hostname you control:
+
+```caddy
+manager.example.com {
+    reverse_proxy nextchair-manager:3000
+}
+```
+
+Reload Caddy after adding the route, then open `/manager`. The Manager has its
+own administrator session and does not use any business customer, staff, or
+owner account.
+
 The MySQL port is loopback-only by default. Use an SSH tunnel for database
 administration rather than opening port 3306 publicly.