fix(ui): default Reduced Motion on Calm and quiet decorative rails (#1622)

* fix(ui): default Reduced Motion on Calm and quiet decorative rails

Calm (and Reset to default) enables Reduced Motion; Signature clears it. Manual Motion stays independent of the visual-style card. Reduced Effects also stops decorative masthead rail animations. Related to #1614; does not close that issue.

* test(e2e): fix Calm Motion specs racing empty-create compose edit

Stop appearance init-script reseeding after mid-test mutations, and wait for Save and Deploy / mobile compose editor after empty create instead of assuming Anatomy Edit compose.

docs/features/appearance.mdx

@@ -45,9 +45,9 @@ The **Chart palette** sets the colors used on the Security page charts:
 
 ## Motion & effects
 
-- **Reduced motion** minimizes interface animations and transitions (dialogs, menus, expand and collapse). Toasts are unaffected. On constrained graphics, this is the first control to try when the active Sencho tab feels heavy on idle.
+- **Reduced motion** minimizes interface animations and transitions (dialogs, menus, expand and collapse). Toasts are unaffected. The **Calm** visual style turns this on by default; choosing **Signature** turns it off. You can still toggle it independently afterward without changing which visual-style card is selected. On constrained graphics, this is the first control to try when the active Sencho tab feels heavy on idle.
 - When Reduced motion is off, Appearance shows a short notice about constrained graphics and points you at Reduced motion.
-- **Reduced effects** flattens card bevels, the accent glow, and chart gradients, and uses a simpler rendering path: glass blur is off and chrome fills are solid. Fresh installs get this through the default **Calm** visual style. Treat it as an optional secondary experiment for material cost; it is not a substitute for Reduced motion on the reported idle-GPU symptom. The impact varies by device, browser, and graphics configuration.
+- **Reduced effects** flattens card bevels, the accent glow, and chart gradients, and uses a simpler rendering path: glass blur is off and chrome fills are solid. It also stops the decorative masthead rail animations even if Reduced motion is off. Fresh installs get this through the default **Calm** visual style. Treat it as an optional secondary experiment for material cost; it is not a substitute for Reduced motion on the reported idle-GPU symptom. The impact varies by device, browser, and graphics configuration.
 - **Ambient glow** sets the intensity of the soft, accent-tinted glow behind the page. Slide it to zero for a completely flat background. (Reduced effects already dims it.)
 
 If the active Sencho tab feels heavy on constrained graphics, see [High GPU usage on constrained graphics](/operations/troubleshooting#high-gpu-usage-on-constrained-graphics).

docs/operations/troubleshooting.mdx

@@ -18,8 +18,8 @@ If something has broken and you want a quick "what do I do now?" overview rather
 **What to try:**
 
 1. Open **Settings → Appearance → Motion & effects**.
-2. Turn on **Reduced motion**. That is the first step to try for high idle GPU use on constrained graphics.
-3. Optionally try **Reduced effects** or **Calm** as a secondary experiment (simpler glass and solid chrome). That path is unverified for this symptom.
+2. Turn on **Reduced motion**. Fresh installs that use **Calm** already enable it by default. That is the first step to try for high idle GPU use on constrained graphics.
+3. Optionally try **Reduced effects** as a secondary experiment (simpler glass, solid chrome, and quieter decorative masthead rails). That path is unverified for the idle-GPU symptom on its own.
 4. On dual-GPU Windows PCs, you can also set the browser's GPU preference to let the OS decide, or prefer a discrete GPU, if your OS exposes that control.
 
 **How to help validate a fix on your hardware:** Identify Chrome's GPU process (Shift+Esc), use Task Manager Details at High update speed on that PID's GPU column, leave the Sencho tab in the foreground for about 15 seconds, then record about ten one-second samples and take the median. Repeat for at least three independent runs (close and reopen the tab). Compare idle Home or Settings with Reduced motion off versus on. Separately compare an update or deploy dialog with Raw output hidden and visible. On Linux single-board devices, use one documented GPU or responsiveness counter for the whole matrix, and label CPU-only readings as secondary.

docs/reference/settings.mdx

@@ -118,8 +118,8 @@ Control how Sencho looks and how dense the workspace feels. Each browser remembe
 | Control | What it does |
 |---------|--------------|
 | **Chart palette** | Colors the Security page charts: **Muted**, **Heat** (one warm ramp), or **Signature** (saturated). |
-| **Reduced motion** | Minimizes interface animations and transitions. First control to try for high idle GPU use on constrained graphics. Toasts are unaffected. |
-| **Reduced effects** | Flattens card bevels, the accent glow, and chart gradients, and turns off glass blur with solid chrome fills. Optional secondary material simplification; not a substitute for Reduced motion on the reported idle-GPU symptom. |
+| **Reduced motion** | Minimizes interface animations and transitions. Calm enables it by default; Signature disables it. Independently toggleable afterward. First control to try for high idle GPU use on constrained graphics. Toasts are unaffected. |
+| **Reduced effects** | Flattens card bevels, the accent glow, and chart gradients, turns off glass blur with solid chrome fills, and stops decorative masthead rail animations. Optional secondary material simplification; not a substitute for Reduced motion on the reported idle-GPU symptom. |
 | **Ambient glow** | Intensity of the accent-tinted page glow. |
 
 ### Theme and typography