Adds DEMO_WALLET_SEED/DEMO_WALLET_HEIGHT support so a demo build restores a
fixed (throwaway, funded) Wownero wallet instead of creating a fresh one, via
WalletRestoreViewModel.create. Balance lives on-chain against the seed, so it
survives any emulator wipe and is reproducible.
Three real bugs fixed on the way:
- build-apk.sh built the --dart-define args as a word-split string; the 16-word
seed's internal spaces split into separate argv tokens and flutter treated a
seed word as a build target ("Target file '<word>' not found"). Now a bash
array keeps each --dart-define one token.
- WalletRestoreViewModel.getCredentials reads name/passphrase from the options
MAP (not the vm field) and casts name as non-null String, so the restore
options must include 'name' and 'passphrase'.
- forward DEMO_WALLET_SEED/HEIGHT into the build container; source demo.env.
Verified end to end: demo build restores the wallet, its address matches the
funded one exactly (QR-decoded), it syncs at height 861800, and the dashboard
shows the real 13.37 WOW balance + tx history. Send shows Max 13.37.
The seed lives only in gitignored tools/demo/demo.env (never committed).
docs/internal-notes.md (gitignored) documents the FailedDecryption gotcha.