Extend genaidlcli to support all AIDL parameter types

Previously the code generator only produced commands for methods with
primitive parameters (50.2% coverage). This extends it to handle:

- Primitive arrays ([]byte as hex, []string as comma-separated, etc.)
- Parcelable struct types with per-field flags and nested struct expansion
- Enum types (type Foo int32) accepting integer values
- binder.IBinder and AIDL interface types via service name lookup
- interface{} and map types via JSON flags
- Nullable (*T) types as optional flags
- Complex array types via JSON fallback

The generator now scans all generated .go files in a type-scanning phase
to build maps of known struct and enum types keyed by import path, then
uses this information to classify each parameter and generate appropriate
flag registration and value extraction code.

Coverage goes from 6160/12258 methods (50.2%) to 12258/12258 (100.0%).

Author: xaionaro@dx.center