Add braceStyle option with same-line (default) and next-line choices.

[motlin]

What changed with this PR:

Added a braceStyle option with two choices:

• same-line (default) — opening braces on the same line (K&R style, existing behavior)
• next-line — opening braces on the next line (Allman style)

This applies to all block constructs: class/interface/enum bodies, method bodies, control flow statements (if/else, for, while, do-while, try/catch/finally, switch, synchronized), static and instance initializers, anonymous classes, lambda blocks, and array initializers.

Example

Input

public class HelloWorld {
    public void greet(String name) {
        if (name != null) {
            System.out.println("Hello, " + name);
        } else {
            System.out.println("Hello, World");
        }
    }
}

Output

With { "braceStyle": "next-line" }:

public class HelloWorld
{
  public void greet(String name)
  {
    if (name != null)
    {
      System.out.println("Hello, " + name);
    }
    else
    {
      System.out.println("Hello, World");
    }
  }
}

Relative issues or prs:

• prettier/prettier#4212 — Option for brace style
• prettier/prettier#3964 — Is it possible to setup "allman" braces style?
• prettier/prettier#3832 — Add option to set braces style