fix(Docs) integrations without conditionals were hidden by default (#15230)

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## Fix: Integrations wrapper incorrectly hidden when no onboarding
options present

### Problem
Regression from #15160 - `integrations: [...]` wrapper was always hidden
by default in code blocks, even when the integrations inside should
always be visible (e.g., `integrations:
[Sentry.captureConsoleIntegration()]`).

The wrapper was only restored to visible by
`updateElementsVisibilityForOptions`, which never runs on pages without
onboarding option buttons.

### Root Cause
In `src/rehype-onboarding-lines.js`, the integrations wrapper was
unconditionally hidden at build time, relying on client-side JavaScript
to show it when appropriate. Pages without `<OnboardingOptionButtons />`
never executed the restore logic.

### Solution
Updated the build-time logic to only hide the integrations wrapper when
**ALL** content inside is conditional (wrapped in
`___PRODUCT_OPTION_START/END___` markers). If any integration is
always-visible (no onboarding option), the wrapper remains visible by
default.

### Scenarios Now Handled Correctly
- ✅ Always-visible integrations only → wrapper always shown
- ✅ All conditional integrations → wrapper hidden/shown based on option
selection
- ✅ Mixed (some always-visible + some conditional) → wrapper always
shown, conditional lines toggle independently
- ✅ Empty inline arrays `integrations: []` → unaffected (not matched by
regex)

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## EXTRA RESOURCES

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Author: sergical

src/rehype-onboarding-lines.js

@@ -58,38 +58,53 @@ function handle_inline_options(node) {
     }
   });
 
+  // Helper to add a class to a line's className property
+  const addClass = (line, className) => {
+    const existing = line.properties.className;
+    line.properties.className = [
+      ...(Array.isArray(existing) ? existing : existing ? [existing] : []),
+      className,
+    ];
+  };
+
   // Second pass: Mark integrations array opening/closing lines
-  // These should be hidden if all content inside is from options that are disabled
+  // Hide wrapper only if ALL content inside is conditional (from onboarding options)
   for (let i = 0; i < (node.children?.length ?? 0); i++) {
     const line = node.children[i];
     const lineStr = toString(line).trim();
 
     // Found "integrations: ["
     if (lineStr.match(/integrations:\s*\[/)) {
-      // Mark the opening line and hide it by default
       line.properties['data-integrations-wrapper'] = 'open';
-      const openClasses = Array.isArray(line.properties.className)
-        ? line.properties.className
-        : line.properties.className
-          ? [line.properties.className]
-          : [];
-      line.properties.className = [...openClasses, 'hidden'];
 
-      // Find the closing "]," - must be exactly ],
+      // Find the closing "],"
+      let closeIndex = -1;
       for (let j = i + 1; j < node.children.length; j++) {
-        const closeStr = toString(node.children[j]).trim();
-        if (closeStr === '],') {
-          // Mark the closing line and hide it by default
+        if (toString(node.children[j]).trim() === '],') {
+          closeIndex = j;
           node.children[j].properties['data-integrations-wrapper'] = 'close';
-          const closeClasses = Array.isArray(node.children[j].properties.className)
-            ? node.children[j].properties.className
-            : node.children[j].properties.className
-              ? [node.children[j].properties.className]
-              : [];
-          node.children[j].properties.className = [...closeClasses, 'hidden'];
           break;
         }
       }
+
+      if (closeIndex === -1) break;
+
+      // Check if ALL content is conditional (has onboarding-option attribute or is a marker)
+      const hasAlwaysVisibleContent = node.children
+        .slice(i + 1, closeIndex)
+        .some(contentLine => {
+          const isMarker = contentLine.properties['data-onboarding-option-hidden'];
+          const hasOption = contentLine.properties['data-onboarding-option'];
+          const hasContent = toString(contentLine).trim();
+          return hasContent && !isMarker && !hasOption;
+        });
+
+      // Only hide wrapper if ALL content is conditional
+      if (!hasAlwaysVisibleContent) {
+        addClass(line, 'hidden');
+        addClass(node.children[closeIndex], 'hidden');
+      }
+
       break; // Only handle first integrations array
     }
   }