fix(gui): make tray initialization non-fatal #188

Context

DROID read-only audit and docs/AUDIT_FIX_CONTINUATION.ru.md note that GUI tray/menu initialization can be fatal through unwrap. Tray availability is platform/environment dependent, so the GUI should continue without tray when tray init fails.

Scope

• Inspect GUI tray/menu initialization code and docs/AUDIT_FIX_CONTINUATION.ru.md context.
• Replace fatal tray init unwraps with graceful fallback/logging.
• Do not change unrelated GUI layout or Android UI behavior.

Acceptance Criteria

• GUI can continue running if tray/menu initialization fails.
• Failure is reported in a non-fatal, privacy-safe way.
• Tests or a focused guard are added where practical.
• cargo test --locked passes.
• cargo clippy --all-targets -- -D warnings passes.
• cargo fmt --check passes.
• cargo build --features gui --locked passes.

Audit Reference

Reported from read-only DROID audit: GUI tray/menu init fatal unwrap path.