feat(ai): expose retained dynamic-tool readiness input

[first-assist]

Summary

• add a purpose-specific retained dynamic-tool readiness input constructor
• bind the exact bootstrap fingerprint, complete nonempty tool surface, model and effort
• release graphql-orm-ai 0.87.0 with migration and security guidance

Security boundary

The constructor only produces validated input. It adds no provider, process, application-tool, egress or result authority. The actor can acknowledge only the probe-marked expected tool with the fixed {\"ready\":true} result, so it cannot carry application data or substitute for an ordinary coordinator result.

Verification

• bounded cargo check -p graphql-orm-ai --features sqlite,provider-codex-app-server
• bounded targeted cargo test -p graphql-orm-ai --features sqlite,provider-codex-app-server --lib retained_dynamic_readiness (2 passed; 312 filtered)
• bounded cargo clippy -p graphql-orm-ai --features sqlite,provider-codex-app-server --lib --no-deps -- -D warnings
• bounded RUSTDOCFLAGS=-D warnings cargo doc -p graphql-orm-ai --features sqlite,provider-codex-app-server --no-deps
• cargo fmt --all -- --check
• python3 scripts/check-documentation.py
• git diff --check

The dependency-inclusive Clippy invocation currently stops on the pre-existing collapsible_else_if lint in graphql-orm-macros/src/operations.rs:4870; the changed crate passes warnings-denied Clippy with --no-deps.

Documentation impact

Updated the crate README, implementation status, changelog and migration guide. No schema, data, GraphQL SDL, protected-payload, backup or restore migration is required.

• Documentation updated
• No documentation impact