main README update

Author: sam-s10s

README.md

@@ -39,7 +39,19 @@ pip install speechmatics-flow
 A Voice Agent Python client for Speechmatics Real-Time API.
 
 ```bash
+# Standard installation
 pip install speechmatics-voice
+
+# With SMART_TURN (ML-based turn detection)
+pip install speechmatics-voice[smart]
+```
+
+### (Beta) TTS Client (`speechmatics-tts`)
+
+An async Python client for Speechmatics TTS API.
+
+```bash
+pip install speechmatics-tts
 ```
 
 ## Development
@@ -60,16 +72,21 @@ speechmatics-python-sdk/
 │   ├── flow/
 │   │   ├── pyproject.toml
 │   │   └── README.md
-│
+│   │
 │   ├── voice/
 │   │   ├── pyproject.toml
 │   │   └── README.md
+│   │
+│   ├── tts/
+│   │   ├── pyproject.toml
+│   │   └── README.md
 │
 ├── tests/
 │   ├── batch/
-│   └── rt/
-│   └── flow/
-│   └── voice/
+│   ├── rt/
+│   ├── flow/
+│   ├── voice/
+│   └── tts/
 │
 ├── examples/
 ├── Makefile
@@ -110,7 +127,8 @@ Each package can be installed separately:
 pip install speechmatics-rt
 pip install speechmatics-batch
 pip install speechmatics-flow
-pip install speechmatics-voice
+pip install speechmatics-voice[smart]
+pip install speechmatics-tts
 ```
 
 ## Docs