fix: restore JSX indentation in design-principles.mdx

The shadcn/ui upgrade (ac37eda) stripped 2-space indentation from JSX
blocks inside preview={} props, leaving them flush-left. This restores
the original indentation style.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: merchako

lib/platform-bible-react/src/stories/guidelines/design-principles.mdx

@@ -114,9 +114,9 @@ Tooltips are required for every icon button and any control without a visible la
     variant="dont"
     previewClassName="tw:pb-8"
     preview={
-<Button variant="outline" size="icon" aria-label="Save" >
-<Save />
-</Button>
+  <Button variant="outline" size="icon" aria-label="Save">
+    <Save />
+  </Button>
 }
   >
     This icon button lacks a tooltip, so users can't learn what it means.
@@ -127,14 +127,14 @@ Tooltips are required for every icon button and any control without a visible la
     variant="dont"
     previewClassName="tw:pb-8"
     preview={
-<TooltipProvider>
-<Tooltip open>
-<TooltipTrigger asChild>
-<Button>Save</Button>
-</TooltipTrigger>
-<TooltipContent side="bottom">Save</TooltipContent>
-</Tooltip>
-</TooltipProvider>
+  <TooltipProvider>
+    <Tooltip open>
+      <TooltipTrigger asChild>
+        <Button>Save</Button>
+      </TooltipTrigger>
+      <TooltipContent side="bottom">Save</TooltipContent>
+    </Tooltip>
+  </TooltipProvider>
 }
   >
     The tooltip only repeats the visible label — omit it.
@@ -148,16 +148,16 @@ Keep tooltip text short enough to scan at a glance. A tooltip is a hint, not an
     variant="dont"
     previewClassName="tw:pb-16"
     preview={
-<TooltipProvider>
-<Tooltip open>
-<TooltipTrigger asChild>
-<Button variant="outline" size="icon" aria-label="Save">
-<Save />
-</Button>
-</TooltipTrigger>
-<TooltipContent side="bottom" className="tw:max-w-[200px]">Click this button to apply your changes and save the current document</TooltipContent>
-</Tooltip>
-</TooltipProvider>
+  <TooltipProvider>
+    <Tooltip open>
+      <TooltipTrigger asChild>
+        <Button variant="outline" size="icon" aria-label="Save">
+          <Save />
+        </Button>
+      </TooltipTrigger>
+      <TooltipContent side="bottom" className="tw:max-w-[200px]">Click this button to apply your changes and save the current document</TooltipContent>
+    </Tooltip>
+  </TooltipProvider>
 }
   >
     Too long to scan — a tooltip is a hint, not a sentence.
@@ -167,16 +167,16 @@ Keep tooltip text short enough to scan at a glance. A tooltip is a hint, not an
     variant="do"
     previewClassName="tw:pb-16"
     preview={
-<TooltipProvider>
-<Tooltip open>
-<TooltipTrigger asChild>
-<Button variant="outline" size="icon" aria-label="Save">
-<Save />
-</Button>
-</TooltipTrigger>
-<TooltipContent side="bottom">Save changes</TooltipContent>
-</Tooltip>
-</TooltipProvider>
+  <TooltipProvider>
+    <Tooltip open>
+      <TooltipTrigger asChild>
+        <Button variant="outline" size="icon" aria-label="Save">
+          <Save />
+        </Button>
+      </TooltipTrigger>
+      <TooltipContent side="bottom">Save changes</TooltipContent>
+    </Tooltip>
+  </TooltipProvider>
 }
   >
     The tooltip adds meaning an icon alone cannot convey, and it's short enough to read at a glance.