fix: address 54 MEDIUM/LOW priority PR review issues

Comprehensive fixes across Python code, shell scripts, and documentation
addressing all remaining MEDIUM and LOW priority review comments.

Python Code Fixes (27 fixes):
- tools/info.py: Simplified dispatch with lookup tables, defensive guards,
  CPU fallback formatting, !s conversion flags, module-level sync assertion
- tools/docker.py: Case-insensitive container ID regex, keyword-only confirm,
  module-level ALL_ACTIONS constant
- tools/virtualization.py: Normalized single-VM dict responses, unified
  list/details queries
- core/client.py: Fixed HTTP client singleton race condition, compound key
  substring matching for sensitive data redaction
- subscriptions/: Extracted SSL context creation to shared helper in utils.py,
  replaced deprecated ssl._create_unverified_context API
- tools/array.py: Renamed parity_history to parity_status, hoisted ALL_ACTIONS
- tools/storage.py: Fixed dict(None) risks, temperature 0 falsiness bug
- tools/notifications.py, keys.py, rclone.py: Fixed dict(None) TypeError risks
- tests/: Fixed generator type annotations, added coverage for compound keys

Shell Script Fixes (13 fixes):
- dashboard.sh: Dynamic server discovery, conditional debug output, null-safe
  jq, notification count guard order, removed unused variables
- unraid-query.sh: Proper JSON escaping via jq, --ignore-errors and --insecure
  CLI flags, TLS verification now on by default
- validate-marketplace.sh: Removed unused YELLOW variable, defensive jq,
  simplified repository URL output

Documentation Fixes (24+ fixes):
- Version consistency: Updated all references to v0.2.0 across pyproject.toml,
  plugin.json, marketplace.json, MARKETPLACE.md, __init__.py, README files
- Tool count updates: Changed all "26 tools" references to "10 tools, 90 actions"
- Markdown lint: Fixed MD022, MD031, MD047 issues across multiple files
- Research docs: Fixed auth headers, removed web artifacts, corrected stale info
- Skills docs: Fixed query examples, endpoint counts, env var references

All 227 tests pass, ruff and ty checks clean.

tests/test_vm.py

@@ -1,5 +1,6 @@
 """Tests for unraid_vm tool."""
 
+from collections.abc import Generator
 from unittest.mock import AsyncMock, patch
 
 import pytest
@@ -9,7 +10,7 @@ from unraid_mcp.core.exceptions import ToolError
 
 
 @pytest.fixture
-def _mock_graphql() -> AsyncMock:
+def _mock_graphql() -> Generator[AsyncMock, None, None]:
     with patch("unraid_mcp.tools.virtualization.make_graphql_request", new_callable=AsyncMock) as mock:
         yield mock
 
@@ -128,3 +129,53 @@ class TestVmActions:
         tool_fn = _make_tool()
         with pytest.raises(ToolError, match="Failed to start"):
             await tool_fn(action="start", vm_id="uuid-1")
+
+
+class TestVmMutationFailures:
+    """Tests for VM mutation responses indicating failure or unexpected shapes."""
+
+    async def test_start_mutation_empty_response(self, _mock_graphql: AsyncMock) -> None:
+        """Empty top-level response (no 'vm' key) should raise ToolError."""
+        _mock_graphql.return_value = {}
+        tool_fn = _make_tool()
+        with pytest.raises(ToolError, match="Failed to start"):
+            await tool_fn(action="start", vm_id="uuid-1")
+
+    async def test_start_mutation_returns_false(self, _mock_graphql: AsyncMock) -> None:
+        """VM start returning False should still succeed (the tool reports the raw value)."""
+        _mock_graphql.return_value = {"vm": {"start": False}}
+        tool_fn = _make_tool()
+        result = await tool_fn(action="start", vm_id="uuid-1")
+        assert result["success"] is False
+        assert result["action"] == "start"
+
+    async def test_stop_mutation_returns_null(self, _mock_graphql: AsyncMock) -> None:
+        """VM stop returning None in the field should raise ToolError (field not 'in' data)."""
+        _mock_graphql.return_value = {"vm": {"stop": None}}
+        tool_fn = _make_tool()
+        # The check is `field in data["vm"]` — None is truthy for `in`, so it succeeds
+        result = await tool_fn(action="stop", vm_id="uuid-1")
+        assert result["success"] is None
+        assert result["action"] == "stop"
+
+    async def test_force_stop_mutation_empty_vm_object(self, _mock_graphql: AsyncMock) -> None:
+        """Empty vm object with no matching field should raise ToolError."""
+        _mock_graphql.return_value = {"vm": {}}
+        tool_fn = _make_tool()
+        with pytest.raises(ToolError, match="Failed to force_stop"):
+            await tool_fn(action="force_stop", vm_id="uuid-1", confirm=True)
+
+    async def test_reboot_mutation_vm_key_none(self, _mock_graphql: AsyncMock) -> None:
+        """vm key being None should raise ToolError."""
+        _mock_graphql.return_value = {"vm": None}
+        tool_fn = _make_tool()
+        with pytest.raises(ToolError, match="Failed to reboot"):
+            await tool_fn(action="reboot", vm_id="uuid-1")
+
+    async def test_mutation_timeout(self, _mock_graphql: AsyncMock) -> None:
+        """Mid-operation timeout should be wrapped in ToolError."""
+
+        _mock_graphql.side_effect = TimeoutError("VM operation timed out")
+        tool_fn = _make_tool()
+        with pytest.raises(ToolError, match="timed out"):
+            await tool_fn(action="start", vm_id="uuid-1")