fix: update spatius avatar token and eof handling

[3DRX]

Summary

• allow Spatius avatar to use either a configured Agora token or generate one from an Agora app certificate
• read Agora config from both top-level properties and params for compatibility
• always send EOF to the avatar on tts_audio_end so interrupted/non-completion reasons do not leave audio open
• bump spatius_avatar_python extension version to 0.1.2

Tests

• task check