Added docs for message types (#118)

* Added docs for message types

* Added docs for message types

* Update depthai_nodes/ml/messages/README.md

Co-authored-by: jkbmrz <74824974+jkbmrz@users.noreply.github.com>

---------

Co-authored-by: jkbmrz <74824974+jkbmrz@users.noreply.github.com>

depthai_nodes/ml/messages/README.md

@@ -1,17 +1,149 @@
-# Implement custom messages in depthai3
+# Message Types
 
-Existing depthai messages that inherit the Buffer class can be extended by:
+Here are the custom message types that we introduce in this package. They are used as output types of the parsers.
 
-```
-import depthai as dai
+**Table of Contents**
 
-class MyCustomMessage(dai.<MessageOfChoice>):
-    def __init__(self):
-        dai.<MessageOfChoice>.__init__(self)
-        self.myField = 42
+- [Classifications](#classifications)
+- [Cluster](#cluster)
+- [Clusters](#clusters)
+- [ImgDetectionExtended](#imgdetectionextended)
+- [ImgDetectionsExtended](#imgdetectionsextended)
+- [Keypoint](#keypoint)
+- [Keypoints](#keypoints)
+- [Line](#line)
+- [Lines](#lines)
+- [Map2d](#map2d)
+- [Prediction](#prediction)
+- [Predictions](#predictions)
+- [SegmentationMask](#segmentationmask)
+- [SegmentationMaskSAM](#segmentationmaskssam)
 
-    def printMe(self):
-        print("My field is", self.myField)
-```
+## Classifications
 
-Note, this does NOT allow for passing to device and back.
+Classification class for storing the classes and their respective scores.
+
+### Attributes
+
+- **classes** (list\[str\]): A list of classes.
+- **scores** (NDArray\[np.float32\]): Corresponding probability scores.
+
+## Cluster
+
+Cluster class for storing a cluster.
+
+### Attributes
+
+- **label** (int): Label of the cluster.
+- **points** (List\[dai.Point2f\]): List of points in the cluster.
+
+## Clusters
+
+Clusters class for storing clusters.
+
+### Attributes
+
+- **clusters** (List\[[Cluster](#cluster)\]): List of clusters.
+
+## ImgDetectionExtended
+
+A class for storing image detections in (x_center, y_center, width, height) format with additional angle and keypoints.
+
+### Attributes
+
+- **x_center** (float): The X coordinate of the center of the bounding box, relative to the input width.
+- **y_center** (float): The Y coordinate of the center of the bounding box, relative to the input height.
+- **width** (float): The width of the bounding box, relative to the input width.
+- **height** (float): The height of the bounding box, relative to the input height.
+- **angle** (float): The angle of the bounding box expressed in degrees.
+- **confidence** (float): Confidence of the detection.
+- **label** (int): Label of the detection.
+- **keypoints** (List\[[Keypoint](#keypoint)\]): Keypoints of the detection.
+
+## ImgDetectionsExtended
+
+ImgDetectionsExtended class for storing image detections with keypoints.
+
+### Attributes
+
+- **detections** (List\[[ImgDetectionExtended](#imgdetectionextended)\]): Image detections with keypoints.
+- **masks** (np.ndarray): The segmentation masks of the image. All masks are stored in a single numpy array.
+
+## Keypoint
+
+Keypoint class for storing a keypoint.
+
+### Attributes
+
+- **x** (float): X coordinate of the keypoint, relative to the input height.
+- **y** (float): Y coordinate of the keypoint, relative to the input width.
+- **z** (Optional\[float\]): Z coordinate of the keypoint.
+- **confidence** (Optional\[float\]): Confidence of the keypoint.
+
+## Keypoints
+
+Keypoints class for storing keypoints.
+
+### Attributes
+
+- **keypoints** (List\[[Keypoint](#keypoint)\]): List of Keypoint objects, each representing a keypoint.
+
+## Line
+
+Line class for storing a line.
+
+### Attributes
+
+- **start_point** (dai.Point2f): Start point of the line with x and y coordinates.
+- **end_point** (dai.Point2f): End point of the line with x and y coordinates.
+- **confidence** (float): Confidence of the line.
+
+## Lines
+
+Lines class for storing lines.
+
+### Attributes
+
+- **lines** (List\[[Line](#line)\]): List of detected lines.
+
+## Map2D
+
+Map2D class for storing a 2D map of floats.
+
+### Attributes
+
+- **map** (NDArray\[np.float32\]): 2D map.
+- **width** (int): 2D Map width.
+- **height** (int): 2D Map height.
+
+## Prediction
+
+Prediction class for storing a prediction.
+
+### Attributes
+
+- **prediction** (float): The predicted value.
+
+## Predictions
+
+Predictions class for storing predictions.
+
+### Attributes
+
+- **predictions** (List\[[Prediction](#prediction)\]): List of predictions.
+
+## SegmentationMask
+
+SegmentationMask class for a single- or multi-object segmentation mask. Background is represented with "-1" and foreground classes with non-negative integers.
+
+### Attributes
+
+- **mask** (NDArray\[np.int8\]): Segmentation mask.
+
+## SegmentationMasksSAM
+
+SegmentationMasksSAM class for storing segmentation masks.
+
+### Attributes
+
+- **masks** (np.ndarray): Mask coefficients.