feat: Add Tenant Telemetry Application Customizer sample

[ValerasNarbutas]

Summary

This PR introduces a new sample: Tenant Telemetry Application Customizer.
The solution provides a lightweight tenant-wide telemetry framework for SPFx solutions, enabling modern monitoring of component usage, page context, versions, and custom events across SharePoint Online.

The Application Customizer listens for browser CustomEvent-based telemetry messages and forwards them—based on configuration—to either Azure Application Insights or a custom Azure Function endpoint.

Key Features

• Tenant-wide Application Customizer for telemetry collection

• TelemetryService supporting two modes:

  • appinsights — direct ingestion via Application Insights Connection String

  • function — POST telemetry to an Azure Function

• Simple integration from web parts via:

  window.dispatchEvent(new CustomEvent("spfx-telemetry", { detail: { ... } }));
  

• Automatic enrichment with:

  • Site URL

  • Page URL

  • Component ID, name, version

• Works across all modern SharePoint sites without modifying existing web parts

• Configurable at runtime using Tenant Wide Extensions

• Includes full TypeScript, localization, and manifest configuration

• Suitable for analytics, usage tracking, component adoption, and operational telemetry

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What's in this Pull Request?

• Added package.json with required dependencies and build scripts

• Added ClientSideInstance.xml and elements.xml for SharePoint integration

• Implemented TelemetryService (App Insights + Azure Function support)

• Implemented TenantTelemetryApplicationCustomizer to initialize telemetry and listen globally for telemetry events

• Included localization support (en-us.js, myStrings.d.ts)

• Configured TypeScript with project-appropriate settings (tsconfig.json)

• Added README documentation, sample usage instructions, and console testing steps

• Included preview image and PnP sample metadata

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PR Metadata

Q	A
Bug fix?	no
New feature?	no
New sample?	yes
Related issues?	#1546

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Additional Notes

This sample demonstrates a scalable pattern for enterprise-grade telemetry collection across thousands of SharePoint Online sites. It enables administrators and developers to understand adoption, diagnose issues, and build richer insights without modifying each web part.

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