refactor(ios-runner): Swift retry decisions keyed on message text → typed codes #2786

Purpose

The runner decides whether to retry by matching message text. AGENTS.md forbids this ("Key behavior on typed reasons and details, never error text"). Paths are under apple/runner/AgentDeviceRunner/AgentDeviceRunnerUITests/; line references are at 01328de411.

• RunnerTests+Lifecycle.swift:402: matches "main thread execution timed out". That text only ever appears in a Swift NSError, never in an ObjC exception, and the exception catcher sees only NSException name and reason (RunnerObjCExceptionCatcher.m:9-13). This branch is dead.
• RunnerTests+Lifecycle.swift:405: in practice this is only reachable from unit tests.
• RunnerTests+Lifecycle.swift:428 (shouldRetryResponse): matches "is not available" against the runner's own response messages (RunnerTests+CommandExecution.swift:1578-1601, 2127-2132).

Required behavior

• Delete the :402 branch.
• Give the responses that :428 needs to retry a typed error code or detail at the place they are produced, and make shouldRetryResponse decide on that field. Keep the retry behavior the same for exactly those responses.
• :405: either key it on the exception name, or delete it with a comment in the PR explaining why it is unreachable.

Completion conditions

• grep -n 'contains("' apple/runner/AgentDeviceRunner/AgentDeviceRunnerUITests/RunnerTests+Lifecycle.swift finds no retry decision based on message text.
• Unit tests pin the retry decision for each typed code.
• Run pnpm check:xctest-selection, build the runner, and run the runner unit tests on the macOS host lane (see docs/agents/testing.md for signing and permissions). Add or change tests under the existing #if AGENT_DEVICE_RUNNER_UNIT_TESTS guard. Do not keep a second list of test names.

Related

TypeScript side: #2787.