feat: MM-150 wallet home screen — identity overview + session status · pull #2

Summary#

Adds load_home_data and log_out Tauri commands in new home.rs module; fires relay health check and getSession concurrently, always returns Ok(HomeData) — partial failures encoded as fields
Implements six Svelte 5 components: DIDAvatar, HomeScreen (identity card + status indicators + action buttons), DIDDocumentScreen (structured view + raw JSON toggle), RecoveryInfoScreen (Shamir share status)
Extends +page.svelte state machine with home, did_document, recovery_info steps; replaces authenticated stub; wires all back-navigation and data-passing callbacks

cargo test -p identity-wallet — 10 new unit tests in home.rs (5 serialization/keychain, 5 httpmock HTTP scenarios); all non-sandbox tests pass; httpmock tests require real network binding (same restriction as pre-existing oauth_client tests)
cargo build -p identity-wallet — clean build, no warnings
pnpm check in apps/identity-wallet/ — 0 errors, 0 warnings
cargo clippy --workspace -- -D warnings — clean
Human verification required — see docs/test-plans/2026-03-27-MM-150.md for iOS Simulator test steps covering all 19 UI/navigation/clipboard acceptance criteria