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/Hip Circles/frames/frame-1.svg

@@ -1,13 +1,35 @@
 <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 320 180" fill="none">
   <title>Hip Circles</title>
+  <defs>
+    <linearGradient id="grad-leg_l-0" gradientUnits="userSpaceOnUse" x1="166.4" y1="96.4" x2="178.0" y2="126.4"><stop offset="0" stop-color="#666c77"/><stop offset="1" stop-color="#717682"/></linearGradient>
+    <linearGradient id="grad-leg_l-1" gradientUnits="userSpaceOnUse" x1="178.0" y1="126.4" x2="164.2" y2="149.3"><stop offset="0" stop-color="#717682"/><stop offset="1" stop-color="#a9afba"/></linearGradient>
+    <linearGradient id="grad-arm_l-1" gradientUnits="userSpaceOnUse" x1="176.9" y1="48.3" x2="182.9" y2="45.2"><stop offset="0" stop-color="#a9afba"/><stop offset="1" stop-color="#979da8"/></linearGradient>
+    <linearGradient id="grad-leg_r-1" gradientUnits="userSpaceOnUse" x1="167.2" y1="127.0" x2="155.8" y2="150.5"><stop offset="0" stop-color="#3a3f4b"/><stop offset="1" stop-color="#a1a7b2"/></linearGradient>
+    <linearGradient id="grad-leg_r-2" gradientUnits="userSpaceOnUse" x1="155.8" y1="150.5" x2="161.8" y2="154.5"><stop offset="0" stop-color="#a1a7b2"/><stop offset="1" stop-color="#585d69"/></linearGradient>
+    <linearGradient id="grad-arm_r-0" gradientUnits="userSpaceOnUse" x1="152.4" y1="38.1" x2="140.3" y2="53.2"><stop offset="0" stop-color="#404551"/><stop offset="1" stop-color="#3a3f4b"/></linearGradient>
+  </defs>
   <path d="M 115.1 151.3 L 180.7 162.7 L 210.4 157.5 L 144.8 146.1 Z" fill="none" stroke="#b9bec9" stroke-width="2.1" stroke-linejoin="round"/>
-  <path id="leg_l" d="M 166.4 96.4 L 178.0 126.4 L 164.2 149.3 L 170.4 153.6" stroke="#a9afba" stroke-width="3.5" stroke-linecap="round" stroke-linejoin="round"/>
-  <path id="arm_l" d="M 166.2 37.1 L 176.9 48.3 L 182.9 45.2" stroke="#a9afba" stroke-width="3.5" stroke-linecap="round" stroke-linejoin="round"/>
-  <path id="leg_r" d="M 156.5 96.6 L 167.2 127.0 L 155.8 150.5 L 161.8 154.5" stroke="#3a3f4b" stroke-width="4.2" stroke-linecap="round" stroke-linejoin="round"/>
+  <g id="leg_l">
+    <path d="M 166.4 96.4 L 178.0 126.4" stroke="url(#grad-leg_l-0)" stroke-width="3.88801" stroke-linecap="round"/>
+    <path d="M 178.0 126.4 L 164.2 149.3" stroke="url(#grad-leg_l-1)" stroke-width="3.67756" stroke-linecap="round"/>
+    <path d="M 164.2 149.3 L 170.4 153.6" stroke="#a9afba" stroke-width="3.5" stroke-linecap="round"/>
+  </g>
+  <g id="arm_l">
+    <path d="M 166.2 37.1 L 176.9 48.3" stroke="#a9afba" stroke-width="3.5" stroke-linecap="round"/>
+    <path d="M 176.9 48.3 L 182.9 45.2" stroke="url(#grad-arm_l-1)" stroke-width="3.55726" stroke-linecap="round"/>
+  </g>
+  <g id="leg_r">
+    <path d="M 156.5 96.6 L 167.2 127.0" stroke="#3a3f4b" stroke-width="4.2" stroke-linecap="round"/>
+    <path d="M 167.2 127.0 L 155.8 150.5" stroke="url(#grad-leg_r-1)" stroke-width="3.8755" stroke-linecap="round"/>
+    <path d="M 155.8 150.5 L 161.8 154.5" stroke="url(#grad-leg_r-2)" stroke-width="3.78096" stroke-linecap="round"/>
+  </g>
   <path id="girdle" d="M 166.2 37.1 L 157.8 37.1 L 152.4 38.1" stroke="#0d9488" stroke-width="3.5" stroke-linecap="round" stroke-linejoin="round"/>
   <path id="pelvisBar" d="M 166.4 96.4 L 160.0 96.0 L 156.5 96.6" stroke="#0d9488" stroke-width="3.5" stroke-linecap="round" stroke-linejoin="round"/>
   <path id="spine" d="M 160.0 96.0 Q 159.6 65.9 157.8 37.1" stroke="#0d9488" stroke-width="4.2" stroke-linecap="round" stroke-linejoin="round"/>
-  <path id="arm_r" d="M 152.4 38.1 L 140.3 53.2 L 159.4 47.8" stroke="#3a3f4b" stroke-width="4.2" stroke-linecap="round" stroke-linejoin="round"/>
+  <g id="arm_r">
+    <path d="M 152.4 38.1 L 140.3 53.2" stroke="url(#grad-arm_r-0)" stroke-width="4.18121" stroke-linecap="round"/>
+    <path d="M 140.3 53.2 L 159.4 47.8" stroke="#3a3f4b" stroke-width="4.2" stroke-linecap="round"/>
+  </g>
   <circle id="head" cx="157.1" cy="23.2" r="7.0" fill="white" stroke="#3a3f4b" stroke-width="4.2"/>
   <line id="nose" x1="164.1" y1="23.8" x2="167.6" y2="24.0" stroke="#3a3f4b" stroke-width="2.8" stroke-linecap="round"/>
   <g font-family="-apple-system, Helvetica, sans-serif" font-size="11" fill="#6b7180">