[FSSDK-12117] upgrade vitest to version 3

[raju-opti]

Issues

• FSSDK-12117

[Copilot]

Pull request overview

This PR upgrades vitest from version 2.0.5 to 3.2.4, which includes updates to the testing framework and its dependencies. The upgrade also includes necessary test fixes that were revealed by the newer version's improved type checking and error detection.

Key Changes:

• Vitest upgraded from v2.0.5 to v3.2.4
• Removed deprecated @vitest/coverage-istanbul package
• Fixed test assertions to use correct property paths
• Corrected package.json export conditions ordering

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated no comments.

File	Description
package.json	Updated vitest version to ^3.2.4, removed @vitest/coverage-istanbul, corrected react_native export order (moved "default" to end per Node.js conventions)
package-lock.json	Updated vitest and related dependencies (esbuild 0.21.5→0.25.12, rollup ~4.40→4.53, tinypool, tinyspy, pathe, etc.) with new v3 peer dependencies
lib/event_processor/event_store.spec.ts	Fixed error constructor calls to use correct property path (event.event.uuid instead of event.id)
lib/core/decision_service/cmab/cmab_client.spec.ts	Fixed error constructor calls to use imported constants instead of string literals

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[coveralls]

coverage: 77.752%. remained the same
when pulling 6dbf2e4 on raju/vitest
into 5d1b6be on master.