Enhance README with a structured layout and logo display

Author: FerrisMind

README.md

@@ -1,7 +1,14 @@
 # iconflow
 
+<table>
+<tr>
+<td width="200" valign="top">
+
 ![iconflow](https://raw.githubusercontent.com/FerrisMind/iconflow/main/assets/icons/iconflow-color.png)
 
+</td>
+<td valign="top">
+
 ## Install
 
 Enable at least one pack feature so the fonts and icon data are included.
@@ -115,3 +122,7 @@ See `docs/faq.md`.
 
 - `cargo xtask gen` regenerates `src/generated/**` from `assets/maps/*.json`.
 - `cargo xtask gen --check` verifies generated output without writing files.
+
+</td>
+</tr>
+</table>