Bond graph ports and drawing added

BEdit/src/bedit/core/power_domains.py

@@ -0,0 +1,31 @@
+"""Editable power-port domain definitions used by the port editor."""
+
+from dataclasses import dataclass
+
+
+@dataclass(frozen=True)
+class PowerDomain:
+    id: str
+    display_name: str
+    effort: str
+    flow: str
+
+
+POWER_DOMAINS: tuple[PowerDomain, ...] = (
+    PowerDomain("power", "Power", "p.e", "p.f"),
+)
+
+
+def power_domain(domain_id: str) -> PowerDomain:
+    return next((domain for domain in POWER_DOMAINS if domain.id == domain_id), POWER_DOMAINS[0])
+
+
+POWER_CAUSALITIES = (
+    "fixed flow out",
+    "fixed effort out",
+    "preferred flow out",
+    "preferred effort out",
+    "likes flow out",
+    "likes effort out",
+    "indifferent",
+)