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/Calfs/frames/frame-1.svg

@@ -1,5 +1,9 @@
 <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 320 180" fill="none">
   <title>Calfs</title>
+  <defs>
+    <linearGradient id="grad-leg_r-1" gradientUnits="userSpaceOnUse" x1="186.0" y1="118.8" x2="212.0" y2="148.8"><stop offset="0" stop-color="#0d9488"/><stop offset="1" stop-color="#11968a"/></linearGradient>
+    <linearGradient id="grad-leg_r-2" gradientUnits="userSpaceOnUse" x1="212.0" y1="148.8" x2="218.7" y2="140.2"><stop offset="0" stop-color="#11968a"/><stop offset="1" stop-color="#0d9488"/></linearGradient>
+  </defs>
   <path d="M 109.6 160.6 L 238.3 160.6 L 238.3 150.2 L 109.6 150.2 Z" fill="none" stroke="#b9bec9" stroke-width="3" stroke-linejoin="round"/>
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   <path d="M 138.0 128.0 L 138.0 150.0" stroke="#c5cad4" stroke-width="5" stroke-linecap="round" stroke-linejoin="round"/>
@@ -7,13 +11,27 @@
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   <path d="M 183.0 62.0 L 183.0 122.0" stroke="#c5cad4" stroke-width="4" stroke-linecap="round" stroke-linejoin="round"/>
   <path d="M 164.0 76.0 L 183.0 76.0" stroke="#6b7180" stroke-width="3" stroke-linecap="round" stroke-linejoin="round"/>
-  <path id="leg_l" d="M 145.9 118.8 L 191.9 116.9 L 216.0 148.3 L 223.2 140.1" stroke="#86cfc5" stroke-width="5" stroke-linecap="round" stroke-linejoin="round"/>
-  <path id="arm_l" d="M 134.1 35.2 L 161.9 46.3 L 170.0 74.8" stroke="#a9afba" stroke-width="5" stroke-linecap="round" stroke-linejoin="round"/>
+  <g id="leg_l">
+    <path d="M 145.9 118.8 L 191.9 116.9" stroke="#86cfc5" stroke-width="5" stroke-linecap="round"/>
+    <path d="M 191.9 116.9 L 216.0 148.3" stroke="#86cfc5" stroke-width="5" stroke-linecap="round"/>
+    <path d="M 216.0 148.3 L 223.2 140.1" stroke="#86cfc5" stroke-width="5" stroke-linecap="round"/>
+  </g>
+  <g id="arm_l">
+    <path d="M 134.1 35.2 L 161.9 46.3" stroke="#a9afba" stroke-width="5" stroke-linecap="round"/>
+    <path d="M 161.9 46.3 L 187.8 31.5" stroke="#a9afba" stroke-width="5" stroke-linecap="round"/>
+  </g>
   <path id="girdle" d="M 134.1 35.2 L 128.1 35.2 L 128.1 37.1" stroke="#3a3f4b" stroke-width="5" stroke-linecap="round" stroke-linejoin="round"/>
   <path id="pelvisBar" d="M 145.9 118.8 L 140.0 118.0 L 140.0 119.2" stroke="#3a3f4b" stroke-width="5" stroke-linecap="round" stroke-linejoin="round"/>
   <path id="spine" d="M 140.0 118.0 Q 131.0 76.0 128.1 35.2" stroke="#3a3f4b" stroke-width="6" stroke-linecap="round" stroke-linejoin="round"/>
-  <path id="leg_r" d="M 140.0 119.2 L 186.0 118.8 L 212.0 148.8 L 218.7 140.2" stroke="#0d9488" stroke-width="6" stroke-linecap="round" stroke-linejoin="round"/>
-  <path id="arm_r" d="M 128.1 37.1 L 155.7 48.8 L 166.0 76.6" stroke="#3a3f4b" stroke-width="6" stroke-linecap="round" stroke-linejoin="round"/>
+  <g id="leg_r">
+    <path d="M 140.0 119.2 L 186.0 118.8" stroke="#0d9488" stroke-width="6" stroke-linecap="round"/>
+    <path d="M 186.0 118.8 L 212.0 148.8" stroke="url(#grad-leg_r-1)" stroke-width="5.98397" stroke-linecap="round"/>
+    <path d="M 212.0 148.8 L 218.7 140.2" stroke="url(#grad-leg_r-2)" stroke-width="5.98397" stroke-linecap="round"/>
+  </g>
+  <g id="arm_r">
+    <path d="M 128.1 37.1 L 155.7 48.8" stroke="#3a3f4b" stroke-width="6" stroke-linecap="round"/>
+    <path d="M 155.7 48.8 L 183.3 37.4" stroke="#3a3f4b" stroke-width="6" stroke-linecap="round"/>
+  </g>
   <path d="M 174.9 117.9 L 202.9 117.9" stroke="#6b7180" stroke-width="7" stroke-linecap="round" stroke-linejoin="round"/>
   <path d="M 207.2 150.4 L 220.8 146.7" stroke="#6b7180" stroke-width="5" stroke-linecap="round" stroke-linejoin="round"/>
   <circle id="head" cx="131.6" cy="15.8" r="10" fill="white" stroke="#3a3f4b" stroke-width="6"/>