REST API: Support non-Latin characters in template route regex.

Non-Latin characters are URL-encoded (e.g. `%cf%84%ce%b5%cf%83%cf%84`). Matching `%` in the route ensures templates with non-Latin titles can be properly saved.

Props antonyagrios, mburridge.
Fixes #57329.


git-svn-id: https://develop.svn.wordpress.org/trunk@55294 602fd350-edb4-49c9-b593-d223f7449a82

tests/phpunit/data/themedir1/block-theme-non-latin/index.php

@@ -0,0 +1,4 @@
+<?php
+/**
+ * Block theme.
+ */

tests/phpunit/data/themedir1/block-theme-non-latin/page-1.php

@@ -0,0 +1,3 @@
+<?php
+
+echo 'PHP template for page with ID 1';

tests/phpunit/data/themedir1/block-theme-non-latin/parts/small-header-τεστ.html

@@ -0,0 +1,3 @@
+<!-- wp:paragraph -->
+<p>Small Header Template Part</p>
+<!-- /wp:paragraph -->

tests/phpunit/data/themedir1/block-theme-non-latin/style.css

@@ -0,0 +1,7 @@
+/*
+Theme Name: Block Theme Non Latin
+Theme URI: https://wordpress.org/
+Description: Has different characters in theme directory name for testing purposes.
+Version: 0.0.1
+Text Domain: block-theme
+*/

tests/phpunit/data/themedir1/block-theme-non-latin/templates/page-τεστ.html

@@ -0,0 +1,3 @@
+<!-- wp:paragraph -->
+<p>(τεστ) Page Template</p>
+<!-- /wp:paragraph -->

tests/phpunit/data/themedir1/block-theme-non-latin/templates/page-测试.html

@@ -0,0 +1,3 @@
+<!-- wp:paragraph -->
+<p>(测试) Page Template</p>
+<!-- /wp:paragraph -->

tests/phpunit/data/themedir1/block-theme-non-latin/theme.json

@@ -0,0 +1,80 @@
+{
+	"version": 1,
+	"settings": {
+		"color": {
+			"palette": [
+				{
+					"slug": "light",
+					"name": "Light",
+					"color": "#f5f7f9"
+				},
+				{
+					"slug": "dark",
+					"name": "Dark",
+					"color": "#000"
+				}
+			],
+			"gradients": [
+				{
+					"name": "Custom gradient",
+					"gradient": "linear-gradient(135deg,rgba(0,0,0) 0%,rgb(0,0,0) 100%)",
+					"slug": "custom-gradient"
+				}
+			],
+			"custom": false,
+			"customGradient": false
+		},
+		"typography": {
+			"fontSizes": [
+				{
+					"name": "Custom",
+					"slug": "custom",
+					"size": "100px"
+				}
+			],
+			"customFontSize": false,
+			"customLineHeight": true
+		},
+		"spacing": {
+			"units": [
+				"rem"
+			],
+			"customPadding": true
+		},
+		"blocks": {
+			"core/paragraph": {
+				"color": {
+					"palette": [
+						{
+							"slug": "light",
+							"name": "Light",
+							"color": "#f5f7f9"
+						}
+					]
+				}
+			}
+		}
+	},
+	"customTemplates": [
+		{
+			"name": "page-τεστ",
+			"title": "Homepage template"
+		},
+		{
+			"name": "page-测试",
+			"title": "Homepage template"
+		}
+	],
+	"templateParts": [
+		{
+			"name": "small-header-τεστ",
+			"title": "Small Header",
+			"area": "header"
+		},
+		{
+			"name": "small-header-测试",
+			"title": "Small Header",
+			"area": "header"
+		},
+	]
+}