Add test infrastructure with Docker services, CLI tools, and resolve Phase 0 questions

Stand up local dev infrastructure (OPC UA, LDAP, MS SQL) with Docker Compose,
Python CLI tools for service interaction, and teardown script. Fix GLAuth config
mount, OPC PLC node format, and document actual DN/namespace behavior discovered
during testing. Resolve Q1-Q8,Q10: .NET 10, Akka.NET 1.5.x, monorepo with slnx,
appsettings JWT, Windows Server 2022 site target.

infra/README.md

@@ -0,0 +1,95 @@
+# ScadaLink Test Infrastructure
+
+Local Docker-based test services for ScadaLink development.
+
+## Quick Start
+
+```bash
+docker compose up -d
+```
+
+This starts three services:
+
+| Service | Port | Purpose |
+|---------|------|---------|
+| OPC UA (Azure IoT OPC PLC) | 50000 (OPC UA), 8080 (web) | Simulated OPC UA server with ScadaLink-style tags |
+| LDAP (GLAuth) | 3893 | Lightweight LDAP with test users/groups matching ScadaLink roles |
+| MS SQL 2022 | 1433 | Configuration and machine data databases |
+
+## First-Time SQL Setup
+
+The MS SQL container does not auto-run init scripts. After the first `docker compose up -d`, run:
+
+```bash
+docker exec -i scadalink-mssql /opt/mssql-tools18/bin/sqlcmd \
+  -S localhost -U sa -P 'ScadaLink_Dev1!' -C \
+  -i /docker-entrypoint-initdb.d/setup.sql
+```
+
+This creates the `ScadaLinkConfig` and `ScadaLinkMachineData` databases and the `scadalink_app` login.
+
+## Stopping & Teardown
+
+**Stop containers** (data persists in SQL volume):
+```bash
+docker compose down
+```
+
+**Stop a single service** (leave the others running):
+```bash
+docker compose stop opcua      # or: ldap, mssql
+docker compose start opcua     # bring it back without recreating
+```
+
+**Full teardown** (stop containers, delete SQL data volume, remove pulled images):
+```bash
+./teardown.sh
+```
+
+Or manually:
+```bash
+docker compose down -v         # stop containers + delete SQL data volume
+docker compose down -v --rmi all  # also remove downloaded images
+```
+
+After a full teardown, the next `docker compose up -d` starts fresh — you'll need to re-run the SQL setup script.
+
+## CLI Tools
+
+Python CLI tools for interacting with the test services are in `tools/`.
+
+**Set up a Python virtual environment** (one-time):
+```bash
+python3 -m venv tools/.venv && source tools/.venv/bin/activate
+```
+
+**Install dependencies** (one-time, with venv active):
+```bash
+pip install -r tools/requirements.txt
+```
+
+> The `.venv` directory is gitignored.
+
+**Quick readiness check** (all three services, with venv active):
+```bash
+python tools/opcua_tool.py check
+python tools/ldap_tool.py check
+python tools/mssql_tool.py check
+```
+
+| Tool | Service | Key Commands |
+|------|---------|-------------|
+| `tools/opcua_tool.py` | OPC UA | `check`, `browse`, `read`, `write`, `monitor` |
+| `tools/ldap_tool.py` | LDAP | `check`, `bind`, `search`, `users`, `groups` |
+| `tools/mssql_tool.py` | MS SQL | `check`, `setup`, `query`, `tables` |
+
+Each tool supports `--help` for full usage. See the per-service docs below for detailed examples.
+
+## Detailed Documentation
+
+See the project root for per-service setup guides:
+
+- [test_infra.md](../test_infra.md) — Master test infrastructure overview
+- [test_infra_opcua.md](../test_infra_opcua.md) — OPC UA server details
+- [test_infra_ldap.md](../test_infra_ldap.md) — LDAP server details
+- [test_infra_db.md](../test_infra_db.md) — MS SQL database details