tooltip (#4242)

# Description of Changes

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- Why the change was made
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## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md#6-testing)
for more details.

frontend/src/components/tooltips/usePageSelectionTips.tsx

@@ -0,0 +1,62 @@
+import { useTranslation } from 'react-i18next';
+import { TooltipContent } from '../../types/tips';
+
+/**
+ * Reusable tooltip for page selection functionality.
+ * Can be used by any tool that uses the GeneralUtils.parsePageList syntax.
+ */
+export const usePageSelectionTips = (): TooltipContent => {
+  const { t } = useTranslation();
+
+  return {
+    header: {
+      title: t("pageSelection.tooltip.header.title", "Page Selection Guide")
+    },
+    tips: [
+      {
+        description: t("pageSelection.tooltip.description", "Choose which pages to use for the operation. Supports single pages, ranges, formulas, and the all keyword.")
+      },
+      {
+        title: t("pageSelection.tooltip.individual.title", "Individual Pages"),
+        description: t("pageSelection.tooltip.individual.description", "Enter numbers separated by commas."),
+        bullets: [
+          t("pageSelection.tooltip.individual.bullet1", "<strong>1,3,5</strong> → selects pages 1, 3, 5"),
+          t("pageSelection.tooltip.individual.bullet2", "<strong>2,7,12</strong> → selects pages 2, 7, 12")
+        ]
+      },
+      {
+        title: t("pageSelection.tooltip.ranges.title", "Page Ranges"),
+        description: t("pageSelection.tooltip.ranges.description", "Use - for consecutive pages."),
+        bullets: [
+          t("pageSelection.tooltip.ranges.bullet1", "<strong>3-6</strong> → selects pages 3–6"),
+          t("pageSelection.tooltip.ranges.bullet2", "<strong>10-15</strong> → selects pages 10–15"),
+          t("pageSelection.tooltip.ranges.bullet3", "<strong>5-</strong> → selects pages 5 to end")
+        ]
+      },
+      {
+        title: t("pageSelection.tooltip.mathematical.title", "Mathematical Functions"),
+        description: t("pageSelection.tooltip.mathematical.description", "Use n in formulas for patterns."),
+        bullets: [
+		  t("pageSelection.tooltip.mathematical.bullet2", "<strong>2n-1</strong> → all odd pages (1, 3, 5…)"),
+          t("pageSelection.tooltip.mathematical.bullet1", "<strong>2n</strong> → all even pages (2, 4, 6…)"),
+          t("pageSelection.tooltip.mathematical.bullet3", "<strong>3n</strong> → every 3rd page (3, 6, 9…)"),
+          t("pageSelection.tooltip.mathematical.bullet4", "<strong>4n-1</strong> → pages 3, 7, 11, 15…")
+        ]
+      },
+      {
+        title: t("pageSelection.tooltip.special.title", "Special Keywords"),
+        bullets: [
+          t("pageSelection.tooltip.special.bullet1", "<strong>all</strong> → selects all pages"),
+        ]
+      },
+      {
+        title: t("pageSelection.tooltip.complex.title", "Complex Combinations"),
+        description: t("pageSelection.tooltip.complex.description", "Mix different types."),
+        bullets: [
+          t("pageSelection.tooltip.complex.bullet1", "<strong>1,3-5,8,2n</strong> → pages 1, 3–5, 8, plus evens"),
+          t("pageSelection.tooltip.complex.bullet2", "<strong>10-,2n-1</strong> → from page 10 to end + odd pages")
+        ]
+      }
+    ]
+  };
+};