Prove the install/reinstall/install_source request envelope with a worst-case ledger test #3327

Follow-up 2c from #2879 (step 1 landed in #2916).

Problem

INSTALL_REQUEST_TIMEOUT_MS = 180_000 (packages/command-registry/src/timeout-policy.ts) covers install, reinstall and install_source. Its only basis is a comment ("above the longest platform install subprocess timeout"). On iOS the subprocess bound is IOS_DEVICE_INSTALL_TIMEOUT_MS = 120_000 (packages/platform-apple/src/core/config.ts, used in deployment/runtime.ts). Nothing checks the Android route, any steps before or after the subprocess, or the 30 s daemon-result margin.

Required

• A worst-case ledger test (the Prove request envelopes cover their worst-case work: fold ledger test, prepare handler margin, batch/replay follow-up #2879 pattern) for the iOS device, iOS simulator and Android install routes, asserting elapsed + 30 s <= the resolved envelope for each of the three commands.
• Prove or correct 180_000, and point its comment at the test.