(feat) pug syntax highlighting (#371)

This provides syntax highlighting, but does not fix any diagnostic errors
#106

Author: dummdidumm

packages/svelte-vscode/package.json

@@ -228,21 +228,22 @@
                 "path": "./syntaxes/svelte.tmLanguage.json",
                 "embeddedLanguages": {
                     "text.html": "html",
+                    "text.pug": "jade",
                     "source.css": "css",
                     "source.css.scss": "scss",
                     "source.js": "javascript",
                     "source.ts": "typescript"
                 }
             },
             {
-              "scopeName": "markdown.svelte.codeblock",
-              "path": "./syntaxes/markdown-svelte.json",
-              "injectTo": [
-                "text.html.markdown"
-              ],
-              "embeddedLanguages": {
-                "meta.embedded.block.svelte": "svelte"
-              }
+                "scopeName": "markdown.svelte.codeblock",
+                "path": "./syntaxes/markdown-svelte.json",
+                "injectTo": [
+                    "text.html.markdown"
+                ],
+                "embeddedLanguages": {
+                    "meta.embedded.block.svelte": "svelte"
+                }
             }
         ],
         "commands": [

packages/svelte-vscode/syntaxes/svelte.tmLanguage.json

@@ -5,6 +5,49 @@
     "uuid": "7582b62f-51d9-4a84-8c8d-fc189530faf6",
 
     "patterns": [
+        {
+            "begin": "(<)(template)\\b(?=[^>]*lang=('jade'|\"jade\"|'pug'|\"pug\"))(?![^/>]*/>\\s*$)",
+            "beginCaptures": {
+                "1": {
+                    "name": "punctuation.definition.tag.begin.html"
+                },
+                "2": {
+                    "name": "entity.name.tag.template.html"
+                }
+            },
+            "end": "(</)(template)(>)",
+            "endCaptures": {
+                "1": {
+                    "name": "punctuation.definition.tag.begin.html"
+                },
+                "2": {
+                    "name": "entity.name.tag.template.html"
+                },
+                "3": {
+                    "name": "punctuation.definition.tag.end.html"
+                }
+            },
+            "patterns": [
+                {
+                    "include": "#tag-stuff"
+                },
+                {
+                    "contentName": "text.pug",
+                    "begin": "(>)",
+                    "beginCaptures": {
+                        "1": {
+                            "name": "punctuation.definition.tag.end.html"
+                        }
+                    },
+                    "end": "(?=</template>)",
+                    "patterns": [
+                        {
+                            "include": "text.pug"
+                        }
+                    ]
+                }
+            ]
+        },
         {
             "begin": "(<)(style)\\b(?=[^>]*(?:type=('text/sass'|\"text/sass\")|lang=(sass|'sass'|\"sass\")))(?![^/>]*/>\\s*$)",
             "beginCaptures": {