ui: assorted polish - Vue async fix, OrbitControls passive listeners, path-viewer + motor-view + indicators

- main.js: disable Vue async batching so reactive writes from
  hashchange listeners propagate synchronously (matches Vue 1's older
  default; avoids dropped DRO updates).
- orbit.js: pass {passive:false} to wheel/touch listeners so
  OrbitControls.preventDefault() actually suppresses page panning.
- path-viewer: opaque dark canvas (no flash from page background),
  zero-size guard, ResizeObserver cleanup on destroy.
- motor-view: stop clobbering user edits with controller state.
- estop/indicators/tool-view/path-viewer pug: rename FA4 icons to FA6,
  add viewBox to estop SVG, fix tool-view trailing newline.

src/pug/templates/estop.pug

@@ -2,6 +2,8 @@ script#estop-template(type="text/x-template")
   svg(version="1.1", xmlns:svg="http://www.w3.org/2000/svg",
     xmlns="http://www.w3.org/2000/svg",
     xmlns:xlink="http://www.w3.org/1999/xlink",
+    viewBox="0 0 130 130",
+    preserveAspectRatio="xMidYMid meet",
     width="130", height="130")
       defs
         path#text-path-1(d="m 73.735,673.129 c 0,55.107 44.673,99.780 99.780,99.780 55.107,0 99.780,-44.673 99.780,-99.780 0,-55.107 -44.673,-99.780 -99.780,-99.780 -55.107,0 -99.780,44.673 -99.780,99.780 z")

src/pug/templates/indicators.pug

@@ -6,11 +6,11 @@ script#indicators-template(type="text/x-template")
 
       tr
         td
-         .fa.fa-plus-circle.io
+         .fa.fa-circle-plus.io
         th Hi/+3.3v
         th.separator
         td
-         .fa.fa-minus-circle.io
+         .fa.fa-circle-minus.io
         th Lo/Gnd
         th.separator
         td
@@ -22,7 +22,7 @@ script#indicators-template(type="text/x-template")
         th Inactive
         th.separator
         td
-         .fa.fa-circle-o.io
+         .far.fa-circle.io
         th Tristated/Disabled
 
     table.inputs
@@ -169,14 +169,14 @@ script#indicators-template(type="text/x-template")
 
       tr
         th Motor
-        th(title="Overtemperature fault"): .fa.fa-thermometer-full
+        th(title="Overtemperature fault"): .fa.fa-temperature-full
         th(title="Overcurrent motor channel A") A #[.fa.fa-bolt]
         th(title="Predriver fault motor channel A")
-          | A #[.fa.fa-exclamation-triangle]
+          | A #[.fa.fa-triangle-exclamation]
         th(title="Overcurrent motor channel B") B #[.fa.fa-bolt]
         th(title="Predriver fault motor channel B")
-          | B #[.fa.fa-exclamation-triangle]
-        th(title="Driver communication failure"): .fa.fa-handshake-o
+          | B #[.fa.fa-triangle-exclamation]
+        th(title="Driver communication failure"): .fa.fa-handshake
         th(title="Reset all motor flags")
           .fa.fa-eraser(@click="motor_reset()")
 

src/pug/templates/path-viewer.pug

@@ -3,7 +3,7 @@ script#path-viewer-template(type="text/x-template")
     .path-viewer-toolbar
       .tool-button(title="Toggle path view size.",
         @click="small = !small", :class="{active: !small}")
-        .fa.fa-arrows-alt
+        .fa.fa-up-down-left-right
 
       .tool-button(@click="showTool = !showTool", :class="{active: showTool}",
         title="Show/hide tool.")

src/pug/templates/tool-view.pug

@@ -433,4 +433,4 @@ script#tool-view-template(type="text/x-template")
           | Other settings according to the
           |
           a(href="https://buildbotics.com/upload/vfd/stepperonline-v70.pdf",
-            target="_blank") Stepper Online V70 VFD manual
+            target="_blank") Stepper Online V70 VFD manual