feat: Provide cleanupTitle to trim text contents of title elements

Fixes #2052

docs/04-plugins/cleanupTitle.mdx

@@ -0,0 +1,9 @@
+---
+title: cleanupTitle
+svgo:
+  pluginId: cleanupTitle
+---
+
+Trims the text contents of [`<title>`](https://developer.mozilla.org/docs/Web/SVG/Element/title) elements.
+
+:::

lib/builtin.js

@@ -6,6 +6,7 @@ import * as cleanupEnableBackground from '../plugins/cleanupEnableBackground.js'
 import * as cleanupIds from '../plugins/cleanupIds.js';
 import * as cleanupListOfValues from '../plugins/cleanupListOfValues.js';
 import * as cleanupNumericValues from '../plugins/cleanupNumericValues.js';
+import * as cleanupTitle from '../plugins/cleanupTitle.js';
 import * as collapseGroups from '../plugins/collapseGroups.js';
 import * as convertColors from '../plugins/convertColors.js';
 import * as convertEllipseToCircle from '../plugins/convertEllipseToCircle.js';
@@ -62,6 +63,7 @@ export const builtin = Object.freeze([
   cleanupIds,
   cleanupListOfValues,
   cleanupNumericValues,
+  cleanupTitle,
   collapseGroups,
   convertColors,
   convertEllipseToCircle,

plugins/cleanupTitle.js

@@ -0,0 +1,24 @@
+export const name = 'cleanupTitle';
+export const description = 'trims the text contents of <title> elements';
+
+/**
+ * Trims the text contents of <title> elements.
+ *
+ * @type {import('./plugins-types.js').Plugin<'cleanupTitle'>}
+ */
+export const fn = () => {
+  return {
+    element: {
+      enter: (node) => {
+        if (node.name === 'title') {
+          node.children = node.children.map((child) => {
+            if (child.type === 'text') {
+              child.value = child.value.trim();
+            }
+            return child;
+          });
+        }
+      },
+    },
+  };
+};

plugins/plugins-types.d.ts

@@ -24,6 +24,7 @@ type DefaultPlugins = {
     defaultPx?: boolean;
     convertToPx?: boolean;
   };
+  cleanupTitle: void;
   collapseGroups: void;
   convertColors: {
     currentColor?: boolean | string | RegExp;

test/plugins/cleanupTitle.01.svg.txt

@@ -0,0 +1,11 @@
+<svg xmlns="http://www.w3.org/2000/svg">
+    <title>    A title isn't indented,  but is escaped and terminally trimmed. </title>
+    <g/>
+</svg>
+
+@@@
+
+<svg xmlns="http://www.w3.org/2000/svg">
+    <title>A title isn&apos;t indented,  but is escaped and terminally trimmed.</title>
+    <g/>
+</svg>