feat(dom): add Observable some every and find consumers - #1977

Implement short-circuit predicate consumers while completing upstream teardown before Promise settlement. Algorithm reference: WICG Observable draft.

Validation from the repository root:

• cargo fmt --all
• cargo clippy --workspace --all-targets --all-features -- -D warnings
• cargo nextest run --no-fail-fast

Summary [ 162.147s] 20818 tests run: 20818 passed (9 slow), 19 skipped (32 build jobs / test threads; automatic retries disabled).

Extracted from wpt-misc-fix historical changes: 024e380f4d3ad6b0099538e6956dfa62d55a3ba3.

Stacked prerequisite: #1976.

Reentrancy note: callback indices advance after callback invocation, following the WICG draft. A nested notification sees the current index, and the implementation reads it again afterward to preserve nested increments. Chromium 145 differs on these reentrant cases.