Initial commit: Shelly Manager with Textual CLI, Streamlit UI, and comprehensive .gitignore

Shelly device management app with mDNS/subnet discovery, inventory,
configuration, and mass operations for Gen1/Gen2+ devices.

Includes .gitignore excluding runtime data (device DB, user config),
AI conversation history, build artifacts, and common Python/OS patterns.

.gitignore

@@ -0,0 +1,63 @@
+# ── Python ──────────────────────────────────────────────
+__pycache__/
+*.py[cod]
+*$py.class
+*.egg-info/
+*.egg
+.eggs/
+
+# ── Virtual environments ───────────────────────────────
+.venv/
+venv/
+env/
+ENV/
+
+# ── Build / Distribution ──────────────────────────────
+dist/
+build/
+*.whl
+*.tar.gz
+
+# ── Testing / Coverage ────────────────────────────────
+.pytest_cache/
+.coverage
+.coverage.*
+htmlcov/
+.tox/
+.nox/
+
+# ── Linting / Type checking ──────────────────────────
+.mypy_cache/
+.ruff_cache/
+.pytype/
+
+# ── Runtime data (user-specific, contains device IPs/configs) ─
+data/
+
+# ── AI conversation history ──────────────────────────
+.specstory/
+
+# ── IDE / Editor ─────────────────────────────────────
+.idea/
+.vscode/
+*.swp
+*.swo
+*~
+
+# ── OS ───────────────────────────────────────────────
+.DS_Store
+Thumbs.db
+
+# ── Secrets / Credentials (preventive) ──────────────
+.env
+.env.*
+!.env.example
+*.pem
+*.key
+*.p12
+*.pfx
+credentials.json
+secrets.json
+
+# ── Logs ─────────────────────────────────────────────
+*.log