Per-Wand Joint-Rolle: explizit waehlen wer am T-Stoss durchgeht

Neues UserString-Feld 'dossier_wand_joint_rolle' per wand_axis:
- 'auto' (default): bisherige Logik. Bei beidseitig auto entscheidet die
  Style-Prio (hoehere = durchgehend)
- 'durchgehend': diese Wand ueberschreibt → ich gehe durch, T-Miter wird
  NICHT auf mich angewendet
- 'anstossend': diese Wand stoppt immer am Joint, auch wenn ich Prio-haerter waere

T-Junction-Detection in regen ruft jetzt _wand_should_apply_t_miter:
- my.rolle entscheidet zuerst
- bei my=auto: through.rolle entscheidet
- bei beide=auto: Prio-Vergleich (hoehere Prio = durchgehend)
- Default: T-Miter applied (= ich stoppe am Through)

Frontend: neue Dropdown 'Joint' in WallProperties zwischen Stil und Aufbau:
- Auto (Prio entscheidet)
- Durchgehend
- Anstossend

Backend-Pipeline: _attach_meta + _read_meta um wand_joint_rolle erweitert,
state-JSON sendet 'jointRolle', _update_wall_body handhabt jointRolle-Patch.

rhino/elemente.py

@@ -41,6 +41,7 @@ _KEY_WAND_LAYERS  = "dossier_wand_layers"   # JSON-Liste [{name, dicke, color}]
 _KEY_WAND_LAYER_IDX = "dossier_wand_layer_idx"  # Layer-Index am Volume-Brep
 _KEY_WAND_CHAIN_MEMBERS = "dossier_wand_chain_members"  # JSON-Liste wand_ids einer Polyline-Chain (nur auf wand_volume)
 _KEY_WAND_STYLE_ID = "dossier_wand_style_id"  # Verweis auf Project-Settings wand_styles[].id
+_KEY_WAND_JOINT_ROLLE = "dossier_wand_joint_rolle"  # "auto"|"durchgehend"|"anstossend" — per-Wand Override am T-Joint
 _KEY_DACH_NEIGUNG = "dossier_dach_neigung"  # Grad als string ("30")
 _KEY_DACH_EAVE    = "dossier_dach_eave"     # Index der Traufkante (string)
 _KEY_DACH_TYP     = "dossier_dach_typ"      # "pult"|"sattel"|"walm"|"mansarde"
@@ -3571,6 +3572,34 @@ def _wand_meta_prio(doc, meta):
     except Exception: return 500
 
 
+def _wand_should_apply_t_miter(doc, my_meta, through_wid):
+    """Entscheidet ob ich (T-Stem-Kandidat) am T-Junction zur Through-Wand
+    angeschmiegt werden soll (= T-mitered). Per-Wand Joint-Rolle hat Vorrang
+    vor Prio:
+      - my.rolle='durchgehend': skip miter (ich bin Through, gehe drueber)
+      - my.rolle='anstossend': apply miter (ich stoppe)
+      - my.rolle='auto' + through.rolle='anstossend': skip (through stoppt)
+      - my.rolle='auto' + through.rolle='durchgehend': apply
+      - beide 'auto': Prio entscheidet (hoehere Prio = Through)"""
+    if not my_meta: return True
+    my_rolle = (my_meta.get("wand_joint_rolle") or "auto").lower()
+    if my_rolle == "durchgehend": return False
+    if my_rolle == "anstossend":  return True
+    # auto: schau auf through-wand
+    th_meta = _wand_meta_by_id(doc, through_wid) if through_wid else None
+    if th_meta:
+        th_rolle = (th_meta.get("wand_joint_rolle") or "auto").lower()
+        if th_rolle == "durchgehend": return True   # through ist explizit through
+        if th_rolle == "anstossend":  return False  # through stoppt → ich Through
+        # beide auto → Prio
+        try:
+            if int(_wand_meta_prio(doc, my_meta)) > int(
+                    _wand_meta_prio(doc, th_meta)):
+                return False  # ich hoehere Prio = Through
+        except Exception: pass
+    return True  # Default: T-mitere mich (T-Stem stoppt am Through)
+
+
 def _wand_meta_by_id(doc, wall_id):
     """Kuerzel: liefert das meta-Dict fuer eine wall_id ueber _find_axis."""
     obj = _find_axis(doc, wall_id)
@@ -3884,6 +3913,7 @@ def _attach_meta(obj_attrs, wall_id, type_, geschoss, dicke, uk_over, ok_over,
                   wand_layered=None, wand_layers=None, wand_layer_idx=None,
                   wand_chain_members=None,
                   wand_style_id=None,
+                  wand_joint_rolle=None,
                   aussp_parent=None):
     """User-Strings auf die Object-Attributes setzen."""
     obj_attrs.SetUserString(_KEY_ID,       wall_id)
@@ -4186,6 +4216,12 @@ def _attach_meta(obj_attrs, wall_id, type_, geschoss, dicke, uk_over, ok_over,
             obj_attrs.SetUserString(_KEY_WAND_STYLE_ID,
                                       str(wand_style_id or ""))
         except Exception: pass
+    if wand_joint_rolle is not None:
+        try:
+            rv = str(wand_joint_rolle or "auto").lower()
+            if rv not in ("auto", "durchgehend", "anstossend"): rv = "auto"
+            obj_attrs.SetUserString(_KEY_WAND_JOINT_ROLLE, rv)
+        except Exception: pass
     if wand_chain_members is not None:
         try:
             import json as _json
@@ -4580,6 +4616,7 @@ def _read_meta(obj):
             "wand_layer_idx":    w_layer_idx,
             "wand_chain_members": w_chain_members,
             "wand_style_id":     a.GetUserString(_KEY_WAND_STYLE_ID) or "",
+            "wand_joint_rolle":  (a.GetUserString(_KEY_WAND_JOINT_ROLLE) or "auto").lower(),
             "aussp_parent":      aussp_parent_raw,
         }
     except Exception:
@@ -8363,8 +8400,9 @@ def _regenerate_element_body(doc, element_id, src_obj, meta, geom, geschoss_name
                                               exclude_ids=chain_set)
                     if tj is not None:
                         _oid, b_tan, b_dicke = tj
-                        tm = _t_junction_miter(p_s, out_s, b_tan, b_dicke)
-                        if tm is not None: miter_start = tm
+                        if _wand_should_apply_t_miter(doc, meta, _oid):
+                            tm = _t_junction_miter(p_s, out_s, b_tan, b_dicke)
+                            if tm is not None: miter_start = tm
                 else:
                     # 3+ Joint: ich bin T-Stem wenn meine Tangente NICHT
                     # collinear mit zwei collinearen Partner-Tangenten ist.
@@ -8393,8 +8431,9 @@ def _regenerate_element_body(doc, element_id, src_obj, meta, geom, geschoss_name
                                               exclude_ids=chain_set)
                     if tj is not None:
                         _oid, b_tan, b_dicke = tj
-                        tm = _t_junction_miter(p_e, out_e, b_tan, b_dicke)
-                        if tm is not None: miter_end = tm
+                        if _wand_should_apply_t_miter(doc, meta, _oid):
+                            tm = _t_junction_miter(p_e, out_e, b_tan, b_dicke)
+                            if tm is not None: miter_end = tm
                 else:
                     # 3+ Joint: T-Stem-Erkennung (analog start)
                     _my_t = geom.TangentAtEnd
@@ -9498,6 +9537,7 @@ class ElementeBridge(panel_base.BaseBridge):
                     "layered":  bool(meta.get("wand_layered", False)),
                     "layers":   meta.get("wand_layers", []),
                     "styleId":  meta.get("wand_style_id", "") or "",
+                    "jointRolle": meta.get("wand_joint_rolle", "auto") or "auto",
                 })
             elif meta["type"] == "decke_outline":
                 uk, ok = _resolve_decke_z(doc, meta["geschoss"], meta["dicke"],
@@ -14543,6 +14583,11 @@ class ElementeBridge(panel_base.BaseBridge):
             try:
                 old_chain_members = _find_wall_chain(doc, wall_id)
             except Exception: pass
+        # Joint-Rolle: explizit per-Wand "auto"/"durchgehend"/"anstossend"
+        if old_meta["type"] == "wand_axis" and "jointRolle" in p:
+            new_joint_rolle = p.get("jointRolle") or "auto"
+        else:
+            new_joint_rolle = old_meta.get("wand_joint_rolle", "auto")
         _attach_meta(attrs, wall_id, old_meta["type"], geschoss, dicke,
                      uk_over, ok_over, referenz,
                      neigung=neigung, eave_idx=eave_idx, dach_typ=dach_typ,
@@ -14550,7 +14595,8 @@ class ElementeBridge(panel_base.BaseBridge):
                      dach_variante=dach_variante,
                      wand_layered=wand_layered,
                      wand_layers=wand_layers if wand_layered else [],
-                     wand_style_id=new_style_id if old_meta["type"] == "wand_axis" else None)
+                     wand_style_id=new_style_id if old_meta["type"] == "wand_axis" else None,
+                     wand_joint_rolle=new_joint_rolle if old_meta["type"] == "wand_axis" else None)
         axis_obj.Attributes = attrs
         axis_obj.CommitChanges()
         # Volumen regenerieren (Layer ggf. anpassen)