Refactor Paper Tonic Modern colorscheme and enhance semantic highlighting

- Updated highlights.scm to improve CSS, HTML, and data attribute captures with higher priority.
- Added a new Lua function to display highlight group and color information under the cursor.
- Expanded editor, semantic, syntax, and TreeSitter highlight groups for better visual consistency across languages.
- Created test files for PHP, HTML, CSS, and Lua to validate syntax highlighting.
- Implemented a shell script to test semantic highlights in a Neovim session.
- Simplified colorscheme loading process by removing unnecessary plugin specifications.

test-css.css

@@ -0,0 +1,25 @@
+.my-class {
+    color: red;
+    background-color: blue;
+    font-size: 16px;
+}
+
+#my-id {
+    margin: 10px;
+}
+
+div.special {
+    padding: 5px;
+}
+
+* {
+    box-sizing: border-box;
+}
+
+.parent > .child {
+    display: block;
+}
+
+a:hover {
+    color: green;
+}