docs(misconf): Add reference info on internals of Trivy IaC scanning

docs/docs/references/misconfiguration.md

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+# Architecture
+
+## Overview
+
+The following diagram shows the high-level architecture of misconfiguration scanning.
+
+```mermaid
+graph TD;
+tf[Terraform]
+cf[CloudFormation]
+aws[Live AWS Account]
+k8s[Kubernetes YAML]
+df[Dockerfiles]
+k8sparser[Kubernetes Parser/Scanner]
+dfparser[Dockerfile Parser/Scanner]
+tfparser[Terraform Parser/Scanner]
+cfparser[CloudFormation Parser/Scanner]
+tfadapter[Terraform Adapter]
+cfadapter[CloudFormation Adapter]
+awsadapter[AWS Adapter]
+checks[OPA Engine]
+tf --> tfparser
+cf --> cfparser
+k8s --> k8sparser
+df --> dfparser
+tfparser --> tfadapter
+cfparser --> cfadapter
+aws --> awsadapter
+tfadapter --> checks
+cfadapter --> checks
+awsadapter --> checks
+k8sparser --> checks
+dfparser --> checks
+checks --> Result
+```
+
+## Component breakdown
+
+Trivy Misconfiguration scanner can be divided into the following components as show below.
+
+![misconfig-code-org](../../imgs/misconfig-code-org.jpg)
+
+Trivy is able to obtain input from both IaC and Live Clouds when it comes to misconfiguration scanning. 
+In the case of IaC scanning, language models such as Terraform and CloudFormation are used to build the common model.
+For Live Cloud scanning, API calls are made directly to the Cloud provider and information is obtained. 
+
+Ultimately, Trivy is able to "normalize" the various sources into a single common denominator which is the same across all input methods by which the resource could be constructed.
+
+
+### `pkg/iac` directory
+
+The `pkg/iac` components can be described as follows.
+
+| Component | Description                                                                                                                                                                                 |
+|-----------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| Adapters  | They are responsible for "adapting" language specific model and transforming it into a common object understood by Trivy                                                                    |
+| Providers | Providers "provide" a language specific model to the scanners, thereby enabling the scanner to call the adapter to "adapt" into a common model                                              |
+| Scanners  | Scanners take the input that providers provide and ask the adapters to adapt it into a common object. This common object is then run through with checks and finally the result is obtained |
+
+
+
+
+Furthermore, misconfiguration scanning can be visualized with the following code flow chart.
+
+![misconfig-iac-functioning](../../imgs/misconfig-iac-functioning.jpg)