feat(metrics): add metrics module types

- Create `MetricsResponse` types to handle API responses
- Add support for retrieving system metrics (CPU, memory, disk, network)
- Add support for Typesense-specific memory metrics
- Ensure compatibility with Python 3.11+ and earlier versions

Author: tharropoulos

src/typesense/metrics.py

@@ -0,0 +1,97 @@
+"""
+This module provides functionality for retrieving metrics from the Typesense API.
+
+It contains the Metrics class, which handles API operations for retrieving
+system and Typesense metrics such as CPU, memory, disk, and network usage.
+
+Classes:
+    MetricsResponse: Type definition for metrics response.
+    Metrics: Manages retrieving metrics from the Typesense API.
+
+Dependencies:
+    - typesense.api_call: Provides the ApiCall class for making API requests.
+
+Note: This module uses conditional imports to support both Python 3.11+ and earlier versions.
+"""
+
+import sys
+
+if sys.version_info >= (3, 11):
+    import typing
+else:
+    import typing_extensions as typing
+
+from typesense.api_call import ApiCall
+
+
+class MetricsResponseBase(typing.TypedDict):
+    """
+    Response schema for metrics retrieval.
+
+    This TypedDict includes system metrics like CPU, memory, disk, and network usage,
+    as well as Typesense-specific memory metrics.
+
+    Attributes:
+        system_cpu_active_percentage (str): Overall CPU active percentage.
+        system_disk_total_bytes (str): Total disk space in bytes.
+        system_disk_used_bytes (str): Used disk space in bytes.
+        system_memory_total_bytes (str): Total system memory in bytes.
+        system_memory_used_bytes (str): Used system memory in bytes.
+        system_network_received_bytes (str): Total network bytes received.
+        system_network_sent_bytes (str): Total network bytes sent.
+        typesense_memory_active_bytes (str): Active memory used by Typesense.
+        typesense_memory_allocated_bytes (str): Allocated memory for Typesense.
+        typesense_memory_fragmentation_ratio (str): Memory fragmentation ratio.
+        typesense_memory_mapped_bytes (str): Mapped memory in bytes.
+        typesense_memory_metadata_bytes (str): Memory used for metadata.
+        typesense_memory_resident_bytes (str): Resident memory in bytes.
+        typesense_memory_retained_bytes (str): Retained memory in bytes.
+    """
+
+    system_cpu_active_percentage: str
+    system_disk_total_bytes: str
+    system_disk_used_bytes: str
+    system_memory_total_bytes: str
+    system_memory_used_bytes: str
+    system_network_received_bytes: str
+    system_network_sent_bytes: str
+    typesense_memory_active_bytes: str
+    typesense_memory_allocated_bytes: str
+    typesense_memory_fragmentation_ratio: str
+    typesense_memory_mapped_bytes: str
+    typesense_memory_metadata_bytes: str
+    typesense_memory_resident_bytes: str
+    typesense_memory_retained_bytes: str
+
+
+class MetricsResponse(MetricsResponseBase):
+    """Extended MetricsResponse with optional per-CPU core metrics."""
+
+    system_memory_total_swap_bytes: str
+    system_memory_used_swap_bytes: str
+    system_cpu1_active_percentage: typing.Optional[str]
+    system_cpu2_active_percentage: typing.Optional[str]
+    system_cpu3_active_percentage: typing.Optional[str]
+    system_cpu4_active_percentage: typing.Optional[str]
+    system_cpu5_active_percentage: typing.Optional[str]
+    system_cpu6_active_percentage: typing.Optional[str]
+    system_cpu7_active_percentage: typing.Optional[str]
+    system_cpu8_active_percentage: typing.Optional[str]
+    system_cpu9_active_percentage: typing.Optional[str]
+    system_cpu10_active_percentage: typing.Optional[str]
+    system_cpu11_active_percentage: typing.Optional[str]
+    system_cpu12_active_percentage: typing.Optional[str]
+    system_cpu13_active_percentage: typing.Optional[str]
+    system_cpu14_active_percentage: typing.Optional[str]
+    system_cpu15_active_percentage: typing.Optional[str]
+    system_cpu16_active_percentage: typing.Optional[str]
+    system_cpu17_active_percentage: typing.Optional[str]
+    system_cpu18_active_percentage: typing.Optional[str]
+    system_cpu19_active_percentage: typing.Optional[str]
+    system_cpu20_active_percentage: typing.Optional[str]
+    system_cpu21_active_percentage: typing.Optional[str]
+    system_cpu22_active_percentage: typing.Optional[str]
+    system_cpu23_active_percentage: typing.Optional[str]
+    system_cpu24_active_percentage: typing.Optional[str]
+
+