P42-002: wire truth gate into queryd /sql + /paged SQL paths

The scrum master flagged crates/queryd/src/service.rs across iters 3-5
with the same finding: "raw SQL forwarded to DataFusion without schema
or policy gate; violates PRD §42-002 truth enforcement." Confidence
79-95%, gradient tier auto/dry_run. Applier couldn't touch it — the fix
is larger than 6 lines and crosses crate boundaries.

Hand-fix lands the missing enforcement point:

  - truth: new RuleCondition::FieldContainsAny { field, needles } with
    case-insensitive substring matching. 4 new unit tests cover the
    positive, negative, missing-field, and empty-needles paths.
  - truth: sql_query_guard_store() helper returns a baseline store that
    rejects destructive verbs (DROP/TRUNCATE/DELETE FROM) and empty SQL.
  - queryd: QueryState grows an Arc<TruthStore>; default router() loads
    sql_query_guard_store; new router_with_truth(engine, store) lets
    tests inject a custom store.
  - queryd: sql_policy_check() runs truth.evaluate("sql_query", ctx)
    before hitting DataFusion. Reject/Block actions on matched
    conditions short-circuit to HTTP 403 with the rule's message.
    Both /sql and /paged gated.
  - queryd: 7 new tests cover block/allow/case-insensitive/false-
    positive scenarios. "SELECT deleted_at FROM t" must NOT be rejected
    (substring match is narrow: "delete from", not "delete").

Total: 28 truth tests green (was 24), 7 new queryd policy tests green.
Workspace baseline warnings unchanged at 11.

This is a signal-driven fix the mechanical pipeline couldn't produce
but the scrum master kept asking for. Closes one of four LOOPING files.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/queryd/Cargo.toml

@@ -7,6 +7,7 @@ edition = "2024"
 shared = { path = "../shared" }
 catalogd = { path = "../catalogd" }
 storaged = { path = "../storaged" }
+truth = { path = "../truth" }
 tokio = { workspace = true }
 axum = { workspace = true }
 serde = { workspace = true }