Rename Workers AI Jev and Clef spans from evaluate to decide #25250

Follow getsentry/sentry-conventions#696: gen_ai.evaluate is deprecated in favor of gen_ai.decide.

The Workers AI integration makes evaluate spans for the evaluation models (TypeSafe Jev typesafe/jev* and Cloudflare Clef @cf/cloudflare/clef*). It detects them by model ID.

Target span

• Name: decide <model> (was evaluate <model>)
• Op: gen_ai.decide (was gen_ai.evaluate)
• gen_ai.operation.name: decide (was evaluate)
• No other change. gen_ai.input.messages / gen_ai.output.messages keep type: 'evaluation'.

Scope

• packages/server-utils/src/ai/workers-ai/utils.ts (operation name type, op map, model prefix detection).
• Update the tests: cloudflare-integration-tests suite workers-ai; unit test test/ai/lib/tracing/workers-ai.test.ts; e2e app cloudflare-workers-send-to-sentry.