chore(kicad): migrate project files to kicad 10 format

Open and save the board, project, and project-local state files under
KiCad 10. Bumps board format version 20241229 -> 20260206 with the new
tenting/covering/plugging/capping/filling stackup directives, drops the
removed HPGL plot params, and adds the KiCad 10 schema additions to the
project file (component class settings, IPC-2581 revision fields, ERC
rule keys, tuning-profile DRC keys, netclass meta version 5). Also
captures live editor UI state (active layer, column widths, hierarchy
collapsed list) in the .kicad_prl.

Constraint: Project is now opened with KiCad 10 - cannot be downgraded
Confidence: high
Scope-risk: broad
Directive: Do not edit these files with KiCad 9.x - format is one-way

firstpcb.kicad_prl

@@ -1,6 +1,6 @@
 {
   "board": {
-    "active_layer": 21,
+    "active_layer": 2,
     "active_layer_preset": "",
     "auto_track_width": true,
     "hidden_netclasses": [],
@@ -15,6 +15,7 @@
       "vias": 1.0,
       "zones": 0.6
     },
+    "prototype_zone_fills": false,
     "selection_filter": {
       "dimensions": true,
       "footprints": true,
@@ -54,6 +55,7 @@
     "zone_display_mode": 0
   },
   "git": {
+    "integration_disabled": false,
     "repo_type": "",
     "repo_username": "",
     "ssh_key": ""
@@ -88,16 +90,16 @@
       9
     ],
     "col_widths": [
-      0,
-      0,
-      0,
-      0,
-      0,
-      0,
-      0,
-      0,
-      0,
-      0
+      69,
+      71,
+      94,
+      78,
+      84,
+      97,
+      85,
+      80,
+      42,
+      666
     ],
     "custom_group_rules": [],
     "expanded_rows": [],
@@ -106,16 +108,18 @@
     "filter_text": "",
     "group_by_constraint": false,
     "group_by_netclass": false,
+    "show_time_domain_details": false,
     "show_unconnected_nets": false,
     "show_zero_pad_nets": false,
-    "sort_ascending": true,
-    "sorting_column": 0
+    "sort_ascending": false,
+    "sorting_column": 7
   },
   "open_jobsets": [],
   "project": {
     "files": []
   },
   "schematic": {
+    "hierarchy_collapsed": [],
     "selection_filter": {
       "graphics": true,
       "images": true,
@@ -123,6 +127,7 @@
       "lockedItems": false,
       "otherItems": true,
       "pins": true,
+      "ruleAreas": true,
       "symbols": true,
       "text": true,
       "wires": true