Phase A1: bootstrap Python ci_orchestrator package

- pyproject.toml (hatchling) with ruff/mypy/pytest dev deps
- src/ci_orchestrator/: config, credentials, backends (Protocol + WorkstationVmrunBackend), transport (WinRM via pypsrp, SSH via paramiko)
- CLI entry point with PoC 'wait-ready' subcommand (Windows + Linux guests)
- tests/python/: 35 unit tests, 83% coverage, all backends/transport mocked
- gitea/workflows/lint.yml: new 'python' job (ruff + mypy --strict + pytest --cov-fail-under=70)
- config.example.toml + README setup section + .gitignore Python entries

Neutral VmBackend Protocol prepared for Phase C ESXi extension.
See plans/implementation-plan-A-B.md step A1.

README.md

@@ -146,6 +146,40 @@ Variante **Windows Server 2022**: `*WinBuild2022.ps1` + VMX `F:\CI\Templates\Win
 
 ---
 
+## Python orchestrator (Phase A — in progress)
+
+A new Python 3.11+ rewrite of the orchestrator lives under `src/ci_orchestrator/`.
+Phase A (see [implementation-plan-A-B](plans/implementation-plan-A-B.md)) is on
+branch `feature/python-rewrite-phase-a`.
+
+Quick setup on the Windows host:
+
+```powershell
+# Create venv (one-time)
+python -m venv F:\CI\python\venv
+F:\CI\python\venv\Scripts\python.exe -m pip install --upgrade pip
+F:\CI\python\venv\Scripts\python.exe -m pip install -e ".[dev]"
+
+# Sanity checks
+F:\CI\python\venv\Scripts\python.exe -m ci_orchestrator --help
+F:\CI\python\venv\Scripts\python.exe -m pytest tests\python -q
+F:\CI\python\venv\Scripts\python.exe -m ruff check src tests\python
+F:\CI\python\venv\Scripts\python.exe -m mypy --strict src
+```
+
+Configuration: copy `config.example.toml` to `F:\CI\config.toml` (or set
+`$env:CI_CONFIG`). Environment variables (`CI_ROOT`, `CI_TEMPLATES`, …) override
+the file.
+
+In Phase A1 only the `wait-ready` PoC is wired:
+
+```powershell
+F:\CI\python\venv\Scripts\python.exe -m ci_orchestrator wait-ready `
+    --vmx F:\CI\BuildVMs\smoke\smoke.vmx --guest-os windows --timeout 300
+```
+
+---
+
 ## Setup rapido
 
 ### 1a. Template VM Windows