fix(security): path traversal, timing-safe auth, stale credential bindings

Security:
- Remove /mnt/ from _ALLOWED_LOG_PREFIXES to prevent Unraid share exposure
- Add early .. detection for disk/logs and live/log_tail path validation
- Add /boot/ prefix restriction for flash_backup source_path
- Use hmac.compare_digest for timing-safe API key verification in server.py
- Gate include_traceback on DEBUG log level (no tracebacks in production)

Correctness:
- Re-raise CredentialsNotConfiguredError in health check instead of swallowing
- Fix ups_device query (remove non-existent nominalPower/currentPower fields)

Best practices (BP-01, BP-05, BP-06):
- Add # noqa: ASYNC109 to timeout params in _handle_live and unraid()
- Fix start_array* → start_array in docstring (not in ARRAY_DESTRUCTIVE)
- Remove from __future__ import annotations from snapshot.py
- Replace import-time UNRAID_API_KEY/URL bindings with _settings.ATTR pattern
  in manager.py, snapshot.py, utils.py, diagnostics.py — fixes stale binding
  after apply_runtime_config() post-elicitation (BP-05)

CI/CD:
- Add .github/workflows/ci.yml (5-job pipeline: lint, typecheck, test, version-sync, audit)
- Add fail_under = 80 to [tool.coverage.report]
- Add version sync check to scripts/validate-marketplace.sh

Documentation:
- Sync plugin.json version 1.1.1 → 1.1.2 with pyproject.toml
- Update CLAUDE.md: 3 tools, system domain count 18, scripts comment fix
- Update README.md: 3 tools, security notes
- Update docs/AUTHENTICATION.md: H1 title fix
- Add UNRAID_CREDENTIALS_DIR to .env.example

Bump: 1.1.1 → 1.1.2

Co-Authored-By: Claude <noreply@anthropic.com>

tests/test_storage.py

@@ -64,12 +64,12 @@ class TestStorageValidation:
 
     async def test_logs_rejects_path_traversal(self, _mock_graphql: AsyncMock) -> None:
         tool_fn = _make_tool()
-        # Traversal that escapes /var/log/ to reach /etc/shadow
-        with pytest.raises(ToolError, match="log_path must start with"):
+        # Traversal that escapes /var/log/ — detected by early .. check
+        with pytest.raises(ToolError, match="log_path"):
             await tool_fn(action="disk", subaction="logs", log_path="/var/log/../../etc/shadow")
-        # Traversal that escapes /mnt/ to reach /etc/passwd
-        with pytest.raises(ToolError, match="log_path must start with"):
-            await tool_fn(action="disk", subaction="logs", log_path="/mnt/../etc/passwd")
+        # Traversal via .. — detected by early .. check
+        with pytest.raises(ToolError, match="log_path"):
+            await tool_fn(action="disk", subaction="logs", log_path="/var/log/../etc/passwd")
 
     async def test_logs_allows_valid_paths(self, _mock_graphql: AsyncMock) -> None:
         _mock_graphql.return_value = {"logFile": {"path": "/var/log/syslog", "content": "ok"}}