Add styling BOLD_RESET_FG (black un Jupyter Lab, white un VSCode)

Change use of  BOLD_BLACK_FG to BOLD_RESET_FG for improved visibility

Author: ecastro-capgemini

jjava/src/main/java/org/dflib/jjava/JavaKernel.java

@@ -146,12 +146,12 @@ public JavaKernel(String version) {
         );
 
         this.errorStyler = new StringStyler.Builder()
-                .addPrimaryStyle(TextColor.BOLD_BLACK_FG)
+                .addPrimaryStyle(TextColor.BOLD_RESET_FG)
                 .addSecondaryStyle(TextColor.BOLD_RED_FG)
-                .addHighlightStyle(TextColor.BOLD_BLACK_FG)
+                .addHighlightStyle(TextColor.BOLD_RESET_FG)
                 .addHighlightStyle(TextColor.RED_BG)
                 //TODO map snippet ids to code cells and put the proper line number in the margin here
-                .withLinePrefix(TextColor.BOLD_BLACK_FG + "|   ")
+                .withLinePrefix(TextColor.BOLD_RESET_FG + "|   ")
                 .build();
 
         this.mavenResolver.initImplicitExtensions();

jupyter-jvm-basekernel/src/main/java/org/dflib/jjava/jupyter/kernel/BaseKernel.java

@@ -107,9 +107,9 @@ public BaseKernel(Charset charset) {
         Text.registerAll(this.renderer);
 
         this.errorStyler = new StringStyler.Builder()
-                .addPrimaryStyle(TextColor.BOLD_BLACK_FG)
+                .addPrimaryStyle(TextColor.BOLD_RESET_FG)
                 .addSecondaryStyle(TextColor.BOLD_RED_FG)
-                .addHighlightStyle(TextColor.BOLD_BLACK_FG)
+                .addHighlightStyle(TextColor.BOLD_RESET_FG)
                 .addHighlightStyle(TextColor.RED_BG)
                 .build();
     }

jupyter-jvm-basekernel/src/main/java/org/dflib/jjava/jupyter/kernel/util/TextColor.java

@@ -32,6 +32,8 @@ public enum TextColor {
     WHITE_BG(47),
     RESET_BG(49),
 
+    BOLD_RESET_FG(39, 1),
+
     BOLD(1),
     UNDERLINE(4),
     SWAP_FG_BG(7),