feat(toolbar): add pdf related info & update snippets

[onlyexeption]

Closes #6297

Checklist:

• check topic's TOC/menu and paragraph headings
• Include TOC topic labels in topic content has a valuable update, it's new or considered as preview\ beta
• link to other topics using ../relative/path.md
• at the References section at the end of the topic add links to topics, samples, etc
• reference API documentation instead of adding a section with API

• use valid component names - [Data] Grid, IgxSelectComponent, <igx-combo>
• use spell checker tool (VS Code, Grammarly, Microsoft Editor)
• add inline code blocks for the names of classes / tags / properties
• add language descriptor for the code blocks
• check broken links (use browser add-on)
• check if sample is working and fully visible in the topic
• check if sample is working and fully visible in the StackBlitz
• check if code blocks match the code in StackBlitz demo

• follow SEO guidelines to fill topic's metadata (SEO guidelines)

• do not resolve requested changes (leave that to the reviewer)
• add pending-localization label when the review of the PR is done
• add a member from the localization team to translate it

[Copilot]

Pull request overview

This PR enhances the grid toolbar documentation by adding PDF export functionality alongside the existing Excel and CSV export capabilities. The changes update references, code snippets, and configuration examples to include PDF export throughout the documentation.

• Added PDF export references to the toolbar features list and service imports
• Updated code examples to include IgxPdfExporterService configuration
• Enhanced the exporter component documentation with PDF-specific options and text customization

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated no new comments.

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