chore(main): release 1.18.0

[github-actions]

🤖 I have created a release beep boop

1.18.0 (2026-06-24)

🐛 Bug Fixes

• event_executor: update provider status before invoking API-level handlers (#494) (42d65a5)
• goroutine leaks in event executor shutdown handling (#508) (703d1f8)

✨ New Features

• export EvaluationAPI and simplify provider/client its surface (#511) (7d09980)
• implement isolated API instances (#492) (84afdff)

🧹 Chore

• delete deprecated pkg package (#509) (95d4d71)
• deps: replace google-github-actions/release-please-action action with googleapis/release-please-action v3 (#496) (981609c)
• deps: update actions/cache action to v5 (#501) (55795e8)
• deps: update actions/checkout action to v6 (#497) (0429a24)
• deps: update actions/checkout action to v7 (#512) (f868dc0)
• deps: update actions/checkout digest to df4cb1c (#504) (ed17a45)
• deps: update actions/setup-go action to v6 (#498) (d9440cf)
• deps: update amannn/action-semantic-pull-request action to v6 (#513) (1e5f48b)
• deps: update codecov/codecov-action action to v6 (#502) (1322453)
• deps: update codecov/codecov-action action to v7 (#506) (ec83513)
• deps: update googleapis/release-please-action action to v5 (#499) (a4354fe)
• deps: update marocchino/sticky-pull-request-comment action to v3 (#514) (214b32d)
• deps: update module golang.org/x/sync to v0.21.0 (#505) (949e235)
• deps: update module golang.org/x/text to v0.37.0 (#500) (73988c5)
• make govulncheck non-blocking (#491) (16f2012)

📚 Documentation

• fix inaccuracies in README code examples (#489) (96240cd)
• simplify usage examples in README.md (#510) (953d6f1)

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This PR was generated with Release Please. See documentation.

[toddbaert]

Blocking for now just as a reminder to manually mention the removal off the long-deprecated pkg package.