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/pi_check.py

@@ -14,6 +14,10 @@ from backend.periscopex.models import (
     LayoutGraph,
 )
 from backend.periscopex.passive_rail_check import _is_ic_supply_pin
+from backend.periscopex.pcb_net_match import (
+    normalize_kicad_hierarchy_net,
+    refs_on_matched_net,
+)
 from backend.periscopex.validate import _match_constraints
 
 _LOAD_KEYS = ("i_load_a", "i_load", "iout", "i_out")
@@ -78,15 +82,18 @@ def check_power_integrity(
         cons = _match_constraints(comp.mpn or comp.value, cmap)
         i_load = _i_load(comp)
         for pin_num, net in sorted(comp.pins.items(), key=lambda x: str(x[0])):
-            if not net or net in seen:
+            if not net:
+                continue
+            net_key = normalize_kicad_hierarchy_net(net)
+            if net_key in seen:
                 continue
             if not _is_ic_supply_pin(graph, cons, pin_num, net):
                 continue
-            seen.add(net)
+            seen.add(net_key)
             locals_: list[tuple[str, float]] = []
             bulks: list[tuple[str, float]] = []
             unvalued = 0
-            for cref in graph.components_on_net(net):
+            for cref in refs_on_matched_net(graph, net):
                 ccomp = graph.components.get(cref)
                 if not ccomp:
                     continue
@@ -99,7 +106,8 @@ def check_power_integrity(
                     bulks.append((cref, farads))
                 else:
                     locals_.append((cref, farads))
-            if not locals_ and unvalued == 0:
+            # Any capacitor on the rail (local, bulk, or unvalued) is decoupling.
+            if not locals_ and not bulks and unvalued == 0:
                 rec = f"Add a local decoupling capacitor on {net} at {ref}."
                 facts = f"{ref} supply {net}: 0 local caps (<1 µF); bulk={len(bulks)}."
                 if i_load is not None: