Introduced by the P2.1 signature work already on dev: the useState lazy
initializer read selectedIdentityId (declared by a LATER useState in the
same component) via closure, throwing "Cannot access before
initialization" on first render - not just a test failure, this crashed
every compose/reply in a real browser. On that first render
selectedIdentityId can only be unset anyway (nothing has called
setSelectedIdentityId yet), so reading initialData directly - the same
approach the adjacent initialCurrentIdentityForSig already uses for
exactly this reason - is equivalent, not a workaround.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>