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>

optional-skills/mlops/models/neutts/assets/neutts-cli/pyproject.toml

@@ -0,0 +1,24 @@
+[build-system]
+requires = ["setuptools>=68", "wheel"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "neutts-cli"
+version = "0.1.0"
+description = "Standalone CLI for installing and running NeuTTS locally"
+readme = "README.md"
+requires-python = ">=3.10"
+license = {text = "MIT"}
+authors = [
+  {name = "Hermes Agent Contributors"}
+]
+dependencies = []
+
+[project.scripts]
+neutts = "neutts_cli.cli:main"
+
+[tool.setuptools]
+package-dir = {"" = "src"}
+
+[tool.setuptools.packages.find]
+where = ["src"]