Replace findings list with a tree; filter ESD/PI false positives.

PE-ESD-001 only on J* connector–IC nets (skip NC, unconnected, VSYS/GND/3V3).
PE-PI-001 treats any capacitor on the rail, including KiCad slash prefixes, as
decoupling. Sort findings ERROR then WARNING then INFO, then RULE/RISK/REVIEW/INFO.
Report sidebar is a collapsed expand-on-click tree instead of an all-open list.
GET /report and complete_findings fail-soft and sort the same way.

backend/periscopex/hierarchy.py

@@ -67,12 +67,14 @@ def build_hierarchy(
                 ref_block[g.ref] = bid
     else:
         for net in graph.nets.values():
-            if net.net_type.value != "power":
+            ntype = getattr(net.net_type, "value", net.net_type)
+            if str(ntype) != "power":
                 continue
             ics = [
                 p.component_ref for p in net.pins
                 if (graph.components.get(p.component_ref)
-                    and graph.components[p.component_ref].component_type.value == "ic")
+                    and str(getattr(graph.components[p.component_ref].component_type, "value",
+                                    graph.components[p.component_ref].component_type)) == "ic")
             ]
             if not ics:
                 continue
@@ -103,7 +105,7 @@ def build_hierarchy(
                     break
         comps.append(HierarchyComponent(
             ref=ref,
-            component_type=comp.component_type.value,
+            component_type=str(getattr(comp.component_type, "value", comp.component_type)),
             pins=pins,
             nets=nets,
             block_id=bid,
@@ -120,7 +122,7 @@ def build_hierarchy(
                     break
         hnets.append(HierarchyNet(
             name=name,
-            net_type=net.net_type.value,
+            net_type=str(getattr(net.net_type, "value", net.net_type)),
             components=refs,
             block_id=bid,
         ))
@@ -131,7 +133,7 @@ def check_hierarchy(graph: DesignGraph, plan: FunctionalGroupsReport | None = No
     """FACT: IC pin with an empty net. Skip unnamed power-flags."""
     out: list[Finding] = []
     for ref, comp in sorted(graph.components.items()):
-        if comp.component_type.value != "ic":
+        if str(getattr(comp.component_type, "value", comp.component_type)) != "ic":
             continue
         dangling = [str(n) for n, net in comp.pins.items() if not (net or "").strip()]
         if not dangling: