feat: add telemetry tracking via auth0-client header

[rax7389]

Summary

Adds telemetry tracking to API calls via the Auth0-Client header. Block components declare their identity using useTelemetry() hook, enabling accurate tracking of which component initiated each API request.

Why

To track usage and understand which UI components are making API calls for analytics and debugging purposes.

What

Core Package (packages/core):

• Added TelemetryComponentGetter type and buildTelemetryHeader() function in telemetry.ts
• Updated createProxyFetcher() and createSpaFetcher() to include telemetry header
• Added getComponent parameter threading through createCoreClient(), createMyAccountClient(), createMyOrganizationClient()

React Package (packages/react):

• Added TelemetryProvider and useTelemetry() hook
• Added CSS detection utility (css-detection.ts)
• Integrated telemetry in spa-provider.tsx and proxy-provider.tsx
• Added useTelemetry() to 6 block components

Packages

• packages/core
• packages/react
• examples

Testing

• This change adds unit test coverage
• Tested for both SPA and RWA flows, all example apps working
• All existing and new tests complete without errors

Checklist

• Breaking change
• Requires docs update
• Backward compatible

Contributing

• I have read the Auth0 general contribution guidelines
• I have read the Auth0 Code of Conduct

[codecov-commenter]

Codecov Report

❌ Patch coverage is 99.14530% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.60%. Comparing base (aecf241) to head (f327b96).

Files with missing lines	Patch %	Lines
...src/hooks/shared/use-core-client-initialization.ts	84.61%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #301      +/-   ##
==========================================
+ Coverage   89.47%   89.60%   +0.13%     
==========================================
  Files         156      160       +4     
  Lines       13070    13240     +170     
  Branches     1419     1357      -62     
==========================================
+ Hits        11694    11864     +170     
  Misses       1376     1376              

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[NaveenChand755]

do we have to support opt out option for customers with strict data policies ?

[NaveenChand755]

should this be inside data layer in service hook ?

[rax7389]

service layer would not be an ideal choice to register the component here , because that can be used within multiple public hooks

[NaveenChand755]

why not package name itself ?

[rax7389]

the requirement is to capture all packages that we would have in UI components, we are passing the framework details in separate key for identification

[rax7389]

do we have to support opt out option for customers with strict data policies ?

Good callout yes we should have, added now!!