Fix junction deviation and jerk settings behavior (#14004)

* Fix junction deviation and jerk settings behavior

Process settings now follow the selected printer's junction deviation
configuration. When machine_max_junction_deviation is enabled,
default_junction_deviation is shown and jerk settings are hidden. When
junction deviation is disabled, jerk settings are restored and
default_junction_deviation is hidden.

Fix a validation issue where junction deviation mismatch warnings could
be reported even when machine_max_junction_deviation was set to 0.
Warnings now apply only when junction deviation is active and point
directly to default_junction_deviation.

Also simplify Motion ability page visibility checks by reusing local
firmware-flavor booleans.

* GUI tweak

- separate Junction Deviation segment
- JD and Jerk stay visible

resources/images/param_junction_deviation.svg

@@ -0,0 +1,10 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="18" height="18" viewBox="0 0 18 18">
+  <line x1="0.5" y1="4.5" x2="7.5" y2="4.5" style="fill:none;stroke:#949494;stroke-linecap:square;stroke-linejoin:round"/>
+  <line x1="15.5" y1="4.5" x2="16.5" y2="4.5" style="fill:none;stroke:#949494;stroke-linecap:square;stroke-linejoin:round"/>
+  <rect x="7.5" y="0.5" width="8" height="13" rx="1" style="fill:none;stroke:#949494;stroke-linecap:round;stroke-linejoin:round"/>
+  <circle cx="11.5" cy="7.5" r="2" style="fill:none;stroke:#949494;stroke-linecap:round;stroke-linejoin:round"/>
+  <polyline points="9.5 13.5 11.5 16.5 13.5 13.5" style="fill:none;stroke:#949494;stroke-linecap:round;stroke-linejoin:round"/>
+
+  <path d="M1.5 6.2 L1.5 11.6 C1.5 14.0 3.0 15.5 5.4 15.5 L8.2 15.5"
+        style="fill:none;stroke:#009688;stroke-linecap:round;stroke-linejoin:round"/>
+</svg>