feat: introduce Expressive Code for code block rendering (#476)

* feat: improve code block feature with Expressive Code

* docs: add example Markdown file for visual review

* feat: improve styles of Expressive Code

* fix: errors from the merging

* chore: formatting

* chore: update config

* chore: update dependencies

* fix: fix build error

* fix: minor fixes

* fix: style tweaks

* docs: update example post

* fix: isolate copy button timeouts to avoid cross-button interference

---------

Co-authored-by: Hasenpfote <Hasenpfote36@gmail.com>

src/config.ts

@@ -1,4 +1,5 @@
 import type {
+	ExpressiveCodeConfig,
 	LicenseConfig,
 	NavBarConfig,
 	ProfileConfig,
@@ -81,3 +82,9 @@ export const licenseConfig: LicenseConfig = {
 	name: "CC BY-NC-SA 4.0",
 	url: "https://creativecommons.org/licenses/by-nc-sa/4.0/",
 };
+
+export const expressiveCodeConfig: ExpressiveCodeConfig = {
+	// Note: Some styles (such as background color) are being overridden, see the astro.config.mjs file.
+	// Please select a dark theme, as this blog theme currently only supports dark background color
+	theme: "github-dark",
+};