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.sh

@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+# ================================================================
+# SPS_SKEL - TROs in die BricsCAD-Zeichnung einblenden
+# ================================================================
+# Aufruf:
+#   bash bin/tro_annotate.sh --file mubea.csv --dxf 500573_60_1.dxf --check
+#   bash bin/tro_annotate.sh --file mubea.csv --dxf 500573_60_1.dxf --flow --fb --legend
+#
+# Die CSV-Datei und die Zeichnung werden in $SKEL_DATA gesucht (oder als
+# vollstaendiger Pfad angegeben). Das beschriftete DXF liegt in $SKEL_RESULTS,
+# der gepruefte Lagebezug in $SKEL_CFG.
+#
+# Die Originalzeichnung wird nie veraendert. DWG wird nicht unterstuetzt.
+# ================================================================
+
+set -eu
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+
+# Umgebung setzen (SKEL_DATA, SKEL_RESULTS, SKEL_CFG, SKEL_LIB, PYTHONPATH ...)
+# shellcheck source=/dev/null
+. "$SCRIPT_DIR/setenv.sh" >/dev/null
+
+# Virtuelle Umgebung nutzen (ezdxf und pydantic werden benoetigt)
+if [ -f "$SPS_SKEL/.venv/bin/activate" ]; then
+    # shellcheck source=/dev/null
+    . "$SPS_SKEL/.venv/bin/activate"
+fi
+
+# Python-Interpreter bestimmen
+PY="python3"
+command -v python3 >/dev/null 2>&1 || PY="python"
+
+exec "$PY" "$SKEL_LIB/tro_annotate.py" "$@"