Add TRO annotation tool writing an annotated copy of the drawing

Takes the original DXF, the CSV export and the derived TROs and writes a copy of
the drawing with the TRO information overlaid. The original is never touched.

Per TRO a block marker with attributes, not loose geometry: one block definition
per type (TRO_SYM_<type>), inserted at the plant coordinate, carrying TRO_ID,
TRO_TYPE, FB_BLOCK visibly and ITEMS, CONFIDENCE, SEPARATORS as hidden data.
That makes the result queryable and editable inside BricsCAD, and a corrected
TRO_ID can later feed back into the generator.

Layers follow the colour groups of tro_catalog (TRO_MARKER_sep, _vario, _store,
...) with the group colour as true colour and entities BYLAYER, so the layer
manager filters by TRO type. Flow arrows and the legend get their own layers.

Re-runs are idempotent through XDATA, not layer names: every generated entity is
tagged with the SPS_SKEL_TRO appid and a re-run deletes exactly those. Deleting
by layer would also destroy anything a user had put on the same layer.

Switches follow the other tools; --check reports the registration and what would
be drawn without writing, --flow adds the TRO-level arrows, --fb shows the
function block, --offset and --re-register override the stored transform. DWG is
rejected with a clear message since ezdxf cannot read it.

Verified against the real 23.8 MB drawing: 9 markers on the correct layers with
readable attributes, 15 flow arrows, and a re-run replaces its own 46 entities
instead of duplicating them.

Adds ezdxf to requirements and stores the verified Mubea transform in cfg/.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

bin/tro_annotate.bat

@@ -0,0 +1,33 @@
+@echo off
+REM ================================================================
+REM SPS_SKEL - TROs in die BricsCAD-Zeichnung einblenden
+REM ================================================================
+REM Aufruf:
+REM   bin\tro_annotate.bat --file mubea.csv --dxf 500573_60_1.dxf --check
+REM   bin\tro_annotate.bat --file mubea.csv --dxf 500573_60_1.dxf --flow --fb --legend
+REM
+REM Die CSV-Datei und die Zeichnung werden in %SKEL_DATA% gesucht (oder als
+REM vollstaendiger Pfad angegeben). Das beschriftete DXF liegt in
+REM %SKEL_RESULTS%, der gepruefte Lagebezug in %SKEL_CFG%.
+REM
+REM Die Originalzeichnung wird nie veraendert. DWG wird nicht unterstuetzt.
+REM ================================================================
+
+setlocal
+
+REM Umgebung setzen (SKEL_DATA, SKEL_RESULTS, SKEL_CFG, SKEL_LIB, PYTHONPATH ...)
+call "%~dp0setenv.bat" >nul
+
+REM Virtuelle Umgebung nutzen (ezdxf und pydantic werden benoetigt)
+if exist "%SPS_SKEL%\.venv\Scripts\activate.bat" (
+    call "%SPS_SKEL%\.venv\Scripts\activate.bat"
+)
+
+REM Python-Interpreter bestimmen (py-Launcher bevorzugt, sonst python)
+set "PY=py"
+py --version >nul 2>&1 || set "PY=python"
+
+"%PY%" "%SKEL_LIB%\tro_annotate.py" %*
+set "RC=%ERRORLEVEL%"
+
+endlocal & exit /b %RC%