NBK-164: make DDSQL async queries resilient

[nmuldavin]

Linear

NBK-164 — https://linear.app/datadoghq/issue/NBK-164/implement-more-robust-async-query-client-for-ddsql-queries

Outcome

All DDSQL async query paths share a browser-aligned client for immediate polling, transient fetch retries, progress reporting, cancellation, and query-ID error context.

Acceptance

• A successful running response is followed immediately by the next fetch, with no client-side inter-poll delay, matching the browser.
• Initial query-submission failures are not retried. Fetch responses with status 429, 500, 502, 503, or 504 are retried; other HTTP failures surface immediately.
• Fetch retries match the advanced query browser client's default: 429 retries five times with exponential base delays of 2s, 4s, 8s, 16s, and 30s (the final 32s base capped at 30s); 500/502/503/504 retry twice with 1s and 2s base delays. Every retry adds independently sampled uniform 0–999ms positive jitter, then caps the complete delay at 30s; jitter does not affect the next exponential base.
• X-RateLimit-Remaining and X-RateLimit-Reset affect 429 delays using the browser's rules: comma-separated values are paired, malformed or incomplete pairs are ignored, only exhausted limits (remaining <= 0) count, and the greatest applicable reset delay is used. A header-selected delay above the 30s per-delay cap stops retries rather than retrying early.
• Long-running queries emit progress to stderr after 10 seconds and again after 30 seconds, without writing progress to stdout.
• Fetch errors include the query ID when available.
• The client has no overall elapsed-time deadline; polling ends when AQA returns a terminal state or the caller cancels.

Validation

• cargo test --all --no-fail-fast -- --test-threads=1 — 1,937 tests passed; serial execution avoids unrelated shared-environment test races.
• cargo test commands::advanced_query::tests --no-fail-fast — 24 lifecycle tests passed.
• cargo test commands::ddsql::tests --no-fail-fast — 43 DDSQL integration/unit tests passed.
• cargo clippy --all-targets -- -D warnings — passed.
• cargo fmt --check — passed.
• cargo check --target wasm32-wasip1 --no-default-features --features wasi — passed, including the target-specific non-Send transport future.
• git diff --check — passed.

Not run / automation gaps

• cargo audit — cargo-audit is not installed locally; no dependencies were added.
• Remaining CI cross-platform builds are delegated to the repository workflows.

Material deviations and decisions

• None.

Remaining work or conditions

• CI stabilization and human review. Keep this PR in draft until explicit human approval to mark it ready.