feat: add NeuTTS optional skill + local TTS provider backend

* feat(skills): add bundled neutts optional skill

Add NeuTTS optional skill with CLI scaffold, bootstrap helper, and
sample voice profile. Also fixes skills_hub.py to handle binary
assets (WAV files) during skill installation.

Changes:
- optional-skills/mlops/models/neutts/ — skill + CLI scaffold
- tools/skills_hub.py — binary asset support (read_bytes, write_bytes)
- tests/tools/test_skills_hub.py — regression tests for binary assets

* feat(tts): add NeuTTS as local TTS provider backend

Add NeuTTS as a fourth TTS provider option alongside Edge, ElevenLabs,
and OpenAI. NeuTTS runs fully on-device via neutts_cli — no API key
needed.

Provider behavior:
- Explicit: set tts.provider to 'neutts' in config.yaml
- Fallback: when Edge TTS is unavailable and neutts_cli is installed,
  automatically falls back to NeuTTS instead of failing
- check_tts_requirements() now includes NeuTTS in availability checks

NeuTTS outputs WAV natively. For Telegram voice bubbles, ffmpeg
converts to Opus (same pattern as Edge TTS).

Changes:
- tools/tts_tool.py — _generate_neutts(), _check_neutts_available(),
  provider dispatch, fallback logic, Opus conversion
- hermes_cli/config.py — tts.neutts config defaults

---------

Co-authored-by: unmodeled-tyler <unmodeled.tyler@proton.me>

hermes_cli/config.py

@@ -241,7 +241,7 @@ DEFAULT_CONFIG = {
     
     # Text-to-speech configuration
     "tts": {
-        "provider": "edge",  # "edge" (free) | "elevenlabs" (premium) | "openai"
+        "provider": "edge",  # "edge" (free) | "elevenlabs" (premium) | "openai" | "neutts" (local)
         "edge": {
             "voice": "en-US-AriaNeural",
             # Popular: AriaNeural, JennyNeural, AndrewNeural, BrianNeural, SoniaNeural
@@ -255,6 +255,9 @@ DEFAULT_CONFIG = {
             "voice": "alloy",
             # Voices: alloy, echo, fable, onyx, nova, shimmer
         },
+        "neutts": {
+            "voice": "",  # NeuTTS voice profile name (empty = use default)
+        },
     },
     
     "stt": {