Add Warm-Up and Stretching activity types

Adds WorkoutActivityType.warmUp (HealthKit .preparationAndRecovery) and
.stretching (.flexibility), and retags the six starter splits that were all
mislabeled as Functional Strength:

- Warm-Up:    Upper Body Warm-Up, Lower Body Warm-Up, Morning Wake-Up
- Stretching: Morning Mobility, Full Body Stretch, Evening Stretch

The split editor's activity picker surfaces them automatically (CaseIterable).
Older app versions decode the new raw values as the default type — additive and
not schema-gated, so no quarantine.

Exercise Library/Lateral Raise/frames/frame-2.svg

@@ -1,13 +1,35 @@
 <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 320 180" fill="none">
   <title>Lateral Raise</title>
+  <defs>
+    <linearGradient id="grad-leg_l-0" gradientUnits="userSpaceOnUse" x1="164.9" y1="90.4" x2="168.3" y2="121.9"><stop offset="0" stop-color="#3a3f4b"/><stop offset="1" stop-color="#a9afba"/></linearGradient>
+    <linearGradient id="grad-leg_l-2" gradientUnits="userSpaceOnUse" x1="171.2" y1="149.4" x2="171.2" y2="150.7"><stop offset="0" stop-color="#a9afba"/><stop offset="1" stop-color="#3a3f4b"/></linearGradient>
+    <linearGradient id="grad-leg_r-0" gradientUnits="userSpaceOnUse" x1="155.1" y1="90.4" x2="151.7" y2="121.9"><stop offset="0" stop-color="#3a3f4b"/><stop offset="1" stop-color="#a9afba"/></linearGradient>
+    <linearGradient id="grad-leg_r-2" gradientUnits="userSpaceOnUse" x1="148.8" y1="149.4" x2="148.8" y2="150.7"><stop offset="0" stop-color="#a9afba"/><stop offset="1" stop-color="#3a3f4b"/></linearGradient>
+    <linearGradient id="grad-arm_l-1" gradientUnits="userSpaceOnUse" x1="188.7" y1="32.5" x2="209.2" y2="33.7"><stop offset="0" stop-color="#86cfc5"/><stop offset="1" stop-color="#0d9488"/></linearGradient>
+    <linearGradient id="grad-arm_r-1" gradientUnits="userSpaceOnUse" x1="131.3" y1="32.5" x2="110.8" y2="33.7"><stop offset="0" stop-color="#86cfc5"/><stop offset="1" stop-color="#0d9488"/></linearGradient>
+  </defs>
   <path d="M 139.0 143.8 L 139.0 163.8 L 181.0 163.8 L 181.0 143.8 Z" fill="none" stroke="#b9bec9" stroke-width="2.1" stroke-linejoin="round"/>
-  <path id="leg_l" d="M 164.9 90.4 L 168.3 121.9 L 171.2 149.4 L 171.2 150.7" stroke="#3a3f4b" stroke-width="4.2" stroke-linecap="round" stroke-linejoin="round"/>
-  <path id="leg_r" d="M 155.1 90.4 L 151.7 121.9 L 148.8 149.4 L 148.8 150.7" stroke="#a9afba" stroke-width="3.5" stroke-linecap="round" stroke-linejoin="round"/>
+  <g id="leg_l">
+    <path d="M 164.9 90.4 L 168.3 121.9" stroke="url(#grad-leg_l-0)" stroke-width="3.85" stroke-linecap="round"/>
+    <path d="M 168.3 121.9 L 171.2 149.4" stroke="#a9afba" stroke-width="3.5" stroke-linecap="round"/>
+    <path d="M 171.2 149.4 L 171.2 150.7" stroke="url(#grad-leg_l-2)" stroke-width="3.85" stroke-linecap="round"/>
+  </g>
+  <g id="leg_r">
+    <path d="M 155.1 90.4 L 151.7 121.9" stroke="url(#grad-leg_r-0)" stroke-width="3.85" stroke-linecap="round"/>
+    <path d="M 151.7 121.9 L 148.8 149.4" stroke="#a9afba" stroke-width="3.5" stroke-linecap="round"/>
+    <path d="M 148.8 149.4 L 148.8 150.7" stroke="url(#grad-leg_r-2)" stroke-width="3.85" stroke-linecap="round"/>
+  </g>
   <path id="girdle" d="M 167.7 31.8 L 160.0 31.8 L 152.3 31.8" stroke="#3a3f4b" stroke-width="3.5" stroke-linecap="round" stroke-linejoin="round"/>
   <path id="pelvisBar" d="M 164.9 90.4 L 160.0 90.4 L 155.1 90.4" stroke="#3a3f4b" stroke-width="3.5" stroke-linecap="round" stroke-linejoin="round"/>
   <path id="spine" d="M 160.0 90.4 Q 160.0 60.4 160.0 31.8" stroke="#3a3f4b" stroke-width="4.2" stroke-linecap="round" stroke-linejoin="round"/>
-  <path id="arm_l" d="M 167.7 31.8 L 188.7 32.5 L 209.2 33.7" stroke="#0d9488" stroke-width="4.2" stroke-linecap="round" stroke-linejoin="round"/>
-  <path id="arm_r" d="M 152.3 31.8 L 131.3 32.5 L 110.8 33.7" stroke="#86cfc5" stroke-width="3.5" stroke-linecap="round" stroke-linejoin="round"/>
+  <g id="arm_l">
+    <path d="M 167.7 31.8 L 188.7 32.5" stroke="#86cfc5" stroke-width="3.5" stroke-linecap="round"/>
+    <path d="M 188.7 32.5 L 209.2 33.7" stroke="url(#grad-arm_l-1)" stroke-width="3.85" stroke-linecap="round"/>
+  </g>
+  <g id="arm_r">
+    <path d="M 152.3 31.8 L 131.3 32.5" stroke="#86cfc5" stroke-width="3.5" stroke-linecap="round"/>
+    <path d="M 131.3 32.5 L 110.8 33.7" stroke="url(#grad-arm_r-1)" stroke-width="3.85" stroke-linecap="round"/>
+  </g>
   <path d="M 111.1 38.6 L 110.5 28.8" stroke="#6b7180" stroke-width="2.0999999999999996" stroke-linecap="round" stroke-linejoin="round"/>
   <circle cx="111.1" cy="38.6" r="3.15" fill="#6b7180"/>
   <circle cx="110.5" cy="28.8" r="3.15" fill="#6b7180"/>