doc: add dev notes for java, antlr and python

DEVNOTE.md

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+# Developer Notes
+
+This article tells the details of this project for the developer of this project.
+
+## Java and Antlr
+
+### Java
+
+Before configuring Java, you should know that all Java parts of this project are just for using Antlr.
+Although Antlr provide C#, C++ and etc bindings, but it is written in Java.
+So using Java can completely utilize Antlr, and I can easily get corresponding examples.
+
+Under this premise, you will know the reason why all these project's Java code are written in crude layout.
+There is no Maven, no Gradle and anything like that in this project.
+We just use the most primitive way to build Java code: use Java compiler to compile all Java files into class files, and order Java runtime to execute the main class.
+Because I just want my Java code works. There is no any other expectations.
+
+Also based on this premise, you can use your favorite IDE to process these code freely.
+The only restriction is that you should not break this premise: use primitive way to build these Java code.
+
+After understanding this premise, you now can configure Java.
+The JDK I used is OpenJDK 21.
+It would be okey for you to use any JDK you like, but obviouslly JDK 1.8 is NOT recommended.
+
+### Antlr
+
+Antlr is used in this project to generate parser and lexer.
+After configuring Java, you can configure Antlr.
+Antlr official document will instruct you how to configure Antlr, ideally.
+Basically, after configuring Antlr, you should make sure that there is 2 programs named `antlr4` and `grun` in your environment.
+So that you can correctly execute commands provided in each projects.
+
+The Antlr I used is Antlr 4.13.0.
+It would be okey for you to use any Antlr you like.
+
+## Python
+
+For most Python code written in this project, we use Astral UV to manage them.
+Astral UV is a great tool to manage Python code.
+Before developing with Python code provided in this project, please prepare Astral UV first.