test(client): accelerate service lifecycle tests

[kitlangton]

What

Reduce Client service lifecycle test time by exercising the same polling, probe, contender, backoff, eviction, and stop behavior with an accelerated private timing policy.

The focused lifecycle suite improves from 72.556s to a 4.529s median, saving 68.03s (93.8%) per run.

How

• Add a private identity-keyed timing policy shared by the Effect and Promise service implementations.
• Keep one source of unchanged production defaults: 1s polling, 2s HTTP requests, 5s initial contender spacing, 30s maximum backoff, 120 Effect attempts / 120s Promise deadline, and 50ms stop polling.
• Apply partial accelerated overrides only to fresh test option objects through a WeakMap; public EnsureOptions and package exports are unchanged.
• Scale fixture delays while preserving their ordering relative to contender spacing, so slow winners, failed losers, lock probes, and incompatible-owner races remain real subprocess tests.
• Synchronize tests through actual health requests, contender starts, and repeated stop attempts instead of fixed sleeps.
• Await detached replacement process exits before temporary-directory cleanup.

Scope

This does not replace subprocesses, mock lifecycle operations, reduce retry counts, or alter production service timing. The private timing module is compiled into dist but is not exposed through package exports or public service declarations.

Testing

• Baseline: hyperfine --warmup 1 --runs 3 'bun run test test/service.test.ts test/promise-service.test.ts': 72.556s ± 0.031s
• After simplify: hyperfine --warmup 1 --runs 9 'bun run test test/service.test.ts test/promise-service.test.ts': 4.529s median, 4.468s–5.253s
• bun run test test/service.test.ts test/promise-service.test.ts --rerun-each 10: 190 pass
• Eight lifecycle suites run concurrently in four processes: 152 pass
• Hanging eviction cases repeated 10 times per implementation: 20 pass
• bun run test: 52 pass
• bun typecheck
• bun run build
• Workspace typecheck: 39 packages pass
• Focused Oxlint: 0 errors
• Prettier and git diff --check