Phases 04+05 of #1162. Splits two more concerns out of the orchestrator:
- src/cliproxy/executor/browser-launch-setup.ts (118 LOC):
resolveBrowserLaunchFlags + resolveBrowserRuntime. Encapsulates browser
flag resolution, attach config, blocked-override warning, and runtime
setup including MCP sync.
- src/cliproxy/executor/account-resolution.ts (197 LOC):
resolveRuntimeQuotaMonitorProviders, resolveAccounts (--accounts /
--use / --nickname / OAuth ban-risk warn / default touch),
applyAccountSafetyGuards, touchDefaultAccount.
- New tests: 184 + 430 LOC covering both modules.
index.ts: 1045 -> 895 LOC (-150). resolveRuntimeQuotaMonitorProviders
re-exported from index.ts for __testExports backwards compat. Behavior
unchanged; full suite passes 1824/1824.
Refs #1162