feat(AI): thinking toggle as NOMAD Switch + info tooltip

Address review feedback on the per-model thinking control:
- Use the shared Switch component (matches AI Assistant settings) instead
  of a raw checkbox.
- Label "Thinking:" with a colon to match the adjacent "Model:" label.
- Add an InfoTooltip explaining what thinking does and where the default
  lives. Extend InfoTooltip with optional `position` ('top'|'bottom') and
  `align` ('center'|'right') so it opens downward and expands leftward from
  the right-edge header slot instead of being clipped/crushed against the
  viewport edge. Defaults preserve existing (benchmark page) behavior.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

admin/inertia/components/InfoTooltip.tsx

@@ -4,9 +4,21 @@ import { useState } from 'react'
 interface InfoTooltipProps {
   text: string
   className?: string
+  // Which side of the icon the tooltip pops toward. Defaults to 'top' (existing behavior);
+  // use 'bottom' when the icon sits near the top of the viewport so it isn't clipped.
+  position?: 'top' | 'bottom'
+  // Horizontal anchoring. 'center' (default) centers the bubble on the icon. Use 'right' when
+  // the icon sits near the right edge so the bubble expands leftward into open space instead of
+  // being squeezed against the viewport edge (which forces one-word-per-line wrapping).
+  align?: 'center' | 'right'
 }
 
-export default function InfoTooltip({ text, className = '' }: InfoTooltipProps) {
+export default function InfoTooltip({
+  text,
+  className = '',
+  position = 'top',
+  align = 'center',
+}: InfoTooltipProps) {
   const [isVisible, setIsVisible] = useState(false)
 
   return (
@@ -23,10 +35,24 @@ export default function InfoTooltip({ text, className = '' }: InfoTooltipProps)
         <IconInfoCircle className="w-4 h-4" />
       </button>
       {isVisible && (
-        <div className="absolute bottom-full left-1/2 -translate-x-1/2 mb-2 z-50">
-          <div className="bg-desert-stone-dark text-white text-xs rounded-lg px-3 py-2 max-w-xs whitespace-normal shadow-lg">
+        <div
+          className={`absolute z-50 ${position === 'bottom' ? 'top-full mt-2' : 'bottom-full mb-2'} ${
+            align === 'right' ? 'right-0' : 'left-1/2 -translate-x-1/2'
+          }`}
+        >
+          <div
+            className={`bg-desert-stone-dark text-white text-xs rounded-lg px-3 py-2 whitespace-normal shadow-lg ${
+              align === 'right' ? 'w-64' : 'max-w-xs'
+            }`}
+          >
             {text}
-            <div className="absolute top-full left-1/2 -translate-x-1/2 border-4 border-transparent border-t-desert-stone-dark" />
+            <div
+              className={`absolute border-4 border-transparent ${
+                position === 'bottom'
+                  ? 'bottom-full border-b-desert-stone-dark'
+                  : 'top-full border-t-desert-stone-dark'
+              } ${align === 'right' ? 'right-3' : 'left-1/2 -translate-x-1/2'}`}
+            />
           </div>
         </div>
       )}

admin/inertia/components/chat/index.tsx

@@ -12,6 +12,8 @@ import classNames from '~/lib/classNames'
 import { IconX } from '@tabler/icons-react'
 import { DEFAULT_QUERY_REWRITE_MODEL } from '../../../constants/ollama'
 import { useSystemSetting } from '~/hooks/useSystemSetting'
+import Switch from '~/components/inputs/Switch'
+import InfoTooltip from '~/components/InfoTooltip'
 
 interface ChatProps {
   enabled: boolean
@@ -534,18 +536,19 @@ export default function Chat({
               )}
             </div>
             {selectedModelSupportsThinking && (
-              <label
-                className="flex items-center gap-1.5 text-sm text-text-secondary cursor-pointer select-none"
-                title="When on, this model reasons before answering. Remembered for this model."
-              >
-                <input
-                  type="checkbox"
-                  checked={effectiveThinking(selectedModel)}
-                  onChange={(e) => setModelThinking(selectedModel, e.target.checked)}
-                  className="h-4 w-4 rounded border-border-default text-desert-green focus:ring-desert-green"
+              <div className="flex items-center">
+                <span className="text-sm text-text-secondary select-none">Thinking:</span>
+                <InfoTooltip
+                  position="bottom"
+                  align="right"
+                  text="When on, this model works through its reasoning before answering. Slower, but often better on tricky questions. Your choice is remembered for this model; the default for other models is set in AI Assistant settings."
                 />
-                Thinking
-              </label>
+                <Switch
+                  id="chat-thinking-toggle"
+                  checked={effectiveThinking(selectedModel)}
+                  onChange={(v) => setModelThinking(selectedModel, v)}
+                />
+              </div>
             )}
             {isInModal && (
               <button