feat(google): add Analytics Admin and Data presets

[aryasaatvik]

Summary

Add first-party Google Analytics Admin and Data presets so users can connect GA4 through the existing Google Discovery and standard-user OAuth flow. Both integrations request read-only Analytics access.

Presets

Preset	Discovery API	Representative operation	Health check
Google Analytics Admin	analyticsadmin/v1beta	analyticsadmin.accountSummaries.list	accountSummaries.list
Google Analytics Data	analyticsdata/v1beta	analyticsdata.properties.runReport	Omitted; the API has no stable cheap read

Both presets:

• use https://www.googleapis.com/auth/analytics.readonly without write scopes;
• preserve their service-hosted Discovery URLs;
• participate in Google bundle OAuth and provider-service split mapping;
• appear in the integration picker.

Validation

• bun x vitest run src/providers/google/presets.test.ts src/providers/google/discovery.test.ts — 27 passed
• bun x vitest run src/planner.test.ts — 30 passed
• bun run typecheck --filter=@executor-js/plugin-openapi --filter=@executor-js/plugin-provider-service-split
• changed-file oxlint --deny-warnings
• changed-file oxfmt --check
• bun run lint:changelog-stubs