docs(generics): add detailed explanation of generic type syntax and conventions

WHAT:
- Documented the concept of **generic types** in Java.
- Explained how classes, interfaces, and methods can be parameterized with type placeholders.
- Included syntax example for defining a generic class:
  `class ClassName<T> { ... }`.
- Clarified the conventional single-letter naming for type parameters.

WHY:
- Generics provide type safety by allowing classes and methods to operate on
  user-defined types without sacrificing reusability.
- Avoids repetitive code and eliminates the need for manual casting.
- Understanding type parameter conventions (T, E, K, V, N) ensures readability and consistency.

DETAILS:
- `T` → Type (generic placeholder, most common).
- `E` → Element (used in collections, e.g., `List<E>`).
- `K` → Key (for map keys).
- `V` → Value (for map values).
- `N` → Number (numeric values).
- These conventions are widely adopted in Java standard libraries.

BENEFITS:
- Compile-time type checking prevents runtime `ClassCastException`.
- Code is reusable and flexible, working with multiple types safely.
- Improves readability and consistency across generic implementations.

REAL-WORLD CONTEXT:
- Used heavily in Java Collections Framework (`List<E>`, `Map<K,V>`, etc.).
- Applicable in custom data structures (e.g., `Box<T>`, `Pair<K,V>`).

Signed-off-by: https://github.com/Someshdiwan <[email protected]>

Author: Someshdiwan

Section24JavaGenerics/src/GenericTypes/Generic Types

@@ -1,8 +1,13 @@
+generic types allow you to define a class, interface, or method with placeholders(type parameters) for the
+datatypes they will work with.
+
 The syntax for a generic type is:
 
 class ClassName<T> {
     // Class body
 }
 
 Where T is the type parameter, which can be any valid identifier.
-Conventionally, single-letter names are used for type parameters, such as T for Type, E for Element, K for Key, V for Value, etc.
+
+Conventionally, single-letter names are used for type parameters,
+such as T for Type, E for Element, K for Key, V for Value, etc.