feat(description): add mobile span descriptions

[buenaflor]

Description

Add mobile span description conventions for foreground app starts and UI load spans.

• Describe foreground app starts using the rendered screen.
• Describe non-standalone cold and warm app starts when the parent span carries the rendered screen.
• Describe screen load, initial display, and full display using the segment name.

PR Checklist

• I have run yarn test and verified that the tests pass.
• I have run yarn generate to generate and format code and docs.

If an attribute was added:

• The attribute is in a namespace (e.g. nextjs.function_id, not function_id)
• I have used the correct value for apply_scrubbing (i.e. manual or auto. Use never only for values that should never be scrubbed such as IDs)

If an attribute was deprecated:

• I've followed the policies described in CONTRIBUTING.md

[github-actions]

Semver Impact of This PR

🟡 Minor (new features)

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New Features ✨

Attributes

• Deprecate sentry.frames.* attributes by buenaflor in #500
• Add missing AI legacy aliases from Relay SpanData by vgrozdanic in #498
• Remove gen AI reasoning effort by constantinius in #503
• Deprecate gen AI reasoning effort by constantinius in #502
• Add sentry.pageload.span_id attribute by Lms24 in #495
• Add sentry.relay.ingress and sentry.relay.pipeline by loewenheim in #491
• Expand grpc attributes by lucas-zimerman in #460
• Add file.path and file.size by buenaflor in #458

Other

• (description) Add mobile span descriptions by buenaflor in #507

Internal Changes 🔧

• (attrs) Backport attributes and normalizations from Relay by Dav1dde in #497
• (release) Show version in workflow run title by constantinius in #504

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