feat(ai): add opt-in app-server web search

[first-assist]

Summary

• add a default-disabled with_web_search(bool) launch-profile setting
• project PublicWeb or allowed-domain policy into the closed app-server thread configuration
• admit correlated native web-search start/completion items and expose bounded actions, call IDs, and structured result metadata
• retain every unrelated native-feature disable and reject unsupported blocked-domain policy
• bump graphql-orm-ai to 0.93.0 with migration and operational documentation

Compatibility and custody

Existing registrations and process implementations remain search-disabled. Enabled requests still require the ordinary built-in, budget, WebSearch egress proof, and a request call ceiling. The protocol has no wire-level call cap, so an over-limit start is rejected after notification; completion metadata is post-context audit because provider-hosted results enter model context first.

Documentation impact

• Documentation updated
• No documentation impact

Verification

• full graphql-orm-ai test suite with all provider/local-harness features (400 unit tests plus integration/doc tests)
• warnings-denied Clippy across all provider/local-harness features
• warnings/missing-docs Rustdoc for full features and Pascal GraphQL naming
• Pascal GraphQL naming test
• PostgreSQL-only and SQL Server-only feature checks
• documentation checker, format check, release-policy check, and cargo-semver-checks