checkAutoLock() called App::lockWallet(), which early-returns without an
rpc_ handle — so lite wallets, which have no daemon, never idle-locked and
stayed unlocked indefinitely. Route lite through lockLiteWallet() instead,
which locks the backend and tears down the chat session so no decrypted
store / unlocked DB key survives the idle lock. Full-node builds keep
lite_wallet_ null, so the branch is a no-op there and behaviour is unchanged.
The idle timer (last_interaction_, reset on ImGui input at the top of
App::update()) is already build-agnostic, so no other wiring is needed.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>