fix(security): enforce SQL authorization across transports

[farhan-syah]

Summary

Fixes GHSA-rgrf-mv99-jwgv by introducing one transport-neutral SQL authorization boundary for:

• pgwire simple and prepared execution
• HTTP JSON and NDJSON queries
• WebSocket RPC and LIVE subscriptions
• native materialized and lazy SQL execution

Security boundary

• validates access to the selected database before DDL, planning, or metadata exposure
• exhaustively authorizes every protected resource in the final task set, including joins, source/target DML, implicit tasks, clone reads, facets, cursors, EXPLAIN, and subscriptions
• enforces collection ownership, explicit user/role grants, built-in roles, database-role isolation, and superuser-only _system.* access
• runs before triggers, sequences, streams, replay, orchestration, staging, Calvin routing, clone probes, or Data Plane dispatch
• maps denials consistently to HTTP 403, SQLSTATE 42501, WebSocket errors, and native protocol errors
• emits one terminal authorization-denial audit event

Regression coverage

Adds end-to-end coverage for:

• database-scoped API keys
• denied reads and writes with no-mutation assertions
• explicit collection grants
• multi-resource joins
• prepared Parse/Describe metadata protection
• cursors, facets, EXPLAIN, and LIVE SELECT
• WebSocket upgrade, replay, and subscription authorization
• native materialized, lazy, and EXPLAIN authorization

Validation

Passed:

• shared authorization unit tests
• HTTP JSON/NDJSON authorization and baseline suites
• WebSocket authorization, lifecycle, and baseline suites
• native SQL authorization and protocol baseline suites
• pgwire database, grant, tenant-scoping, prepared-query, and API-key scope suites
• focused clone read/copy-up and DDL error-mapping tests
• cargo fmt --all
• cargo clippy --all-targets --all-features -- -D warnings
• bash scripts/ci/check_calvin_determinism.sh
• git diff --check

The separate cluster stage exposed existing Calvin explicit-transaction/OLLP failures unrelated to this authorization boundary; no cluster behavior was changed or included in this PR.