Type JSON response bodies without Any

[adamtheturtle]

Summary

• replace the JSON serializer’s dict-of-Any boundary with the repository’s recursive JSON value type
• use that same recursive type for query results and every heterogeneous response body that reaches the serializer
• remove the associated Pyrefly explicit-Any suppressions without substituting broad object
• initialize the query result before optionally adding target data, fixing the failing include-target-data path from the first revision

The branch is also rebased onto current main so it retains the recently merged request-body typing cleanup.

Validation

• all configured pre-commit hooks
• all configured pre-push hooks, including Mypy, Pyright, Ty, and Pyrefly
• complete query suite against credential-free backends: 162 passed, 81 real-Vuforia cases skipped
• the hosted matrix provides the credentialed real-service, Docker, Windows, and combined 100% coverage gates