[PowerPoint] (Overview) Add article about object model

[ElizabethSamuel-MSFT]

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[learn-build-service-prod]

Learn Build status updates of commit f17742f:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/powerpoint/core-concepts.md	✅Succeeded	View
docs/toc.yml	✅Succeeded	View

For more details, please refer to the build report.

[Copilot]

Pull Request Overview

This PR introduces a new conceptual article on the PowerPoint JavaScript object model and adds it to the PowerPoint TOC.

• Creates core-concepts.md detailing key PowerPoint object model components.
• Updates docs/toc.yml to include the new article in the PowerPoint section.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
docs/toc.yml	Inserts a new TOC entry for the object model
docs/powerpoint/core-concepts.md	Adds a concept article on the PowerPoint object model

Comments suppressed due to low confidence (1)

docs/toc.yml:925

• Indentation for the new TOC entry doesn’t match existing items. Align it with sibling entries by adding two more spaces before the hyphen.

    - name: PowerPoint object model

[learn-build-service-prod]

Learn Build status updates of commit a41e157:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/powerpoint/core-concepts.md	✅Succeeded	View
docs/toc.yml	✅Succeeded	View

For more details, please refer to the build report.