chore: add MCP integration and refactor documentation into modular how-to guides

- Moved GraphQL query samples into a new `docs/queries` directory for better organization.
- Added new queries and mutations, including `createHost.graphql` and `GetApiVersion.graphql`.
- Introduced `mcp-config.yaml` and updated `docker-compose.yml` for MCP integration.
- Updated IntelliJ `.idea/workspace.xml` settings to reflect project changes.
- Added new how-to guides (`docs/howtos`) for permissions, tags, MCP integration, and schema usage.
- Enhanced tests by updating file paths and improving sample data locations.
- Refined permissions and host group structures in `zabbix-hostgroups.ts` and `resolvers.ts`.

docs/howtos/hierarchical_data_mapping.md

@@ -0,0 +1,41 @@
+## 🗂️ Hierarchical Data Mapping
+
+The API automatically maps Zabbix items to nested GraphQL objects using the `createHierarchicalValueFieldResolver` function.
+
+### How it Works
+
+Zabbix item keys are used to define the structure in GraphQL. A dot (`.`) acts as a separator to represent nested object structures.
+
+**Example:**
+Zabbix item key `state.current.values.temperature` is automatically mapped to:
+```json
+{
+  "state": {
+    "current": {
+      "values": {
+        "temperature": 25.5
+      }
+    }
+  }
+}
+```
+
+### Type Hinting
+
+You can guide the type conversion by prepending a type hint and an underscore to the last token of the Zabbix item key:
+
+*   `json_`: Parses the value as a JSON object (useful for complex types).
+*   `str_`: Forces the value to be treated as a string.
+*   `bool_`: Forces the value to be treated as a boolean.
+*   `float_`: Forces the value to be treated as a number.
+
+### Preconditions
+
+1.  **Key Naming**: Zabbix item keys (or tags) must match the GraphQL field names.
+2.  **Dot Separation**: Use dots to represent the desired hierarchy.
+
+The `createHierarchicalValueFieldResolver` function (found in `../../src/api/resolver_helpers.ts`) dynamically creates these resolvers, eliminating the need for manual resolver definitions for each hierarchical field.
+
+For more information, see the comments in `../../schema/device_value_commons.graphql` and `../../src/api/resolver_helpers.ts`.
+
+See `../queries/sample_all_devices_query.graphql` for examples of hierarchical data in query results.