fix(vscode-vipeye): 字符串转义引号导致 TextMate 作用域泄漏

字符串规则没有转义子规则，`'\''` / `"\""` 会被提前闭合：后续关键字
（如 or/def/return/pass）被渲染成字符串颜色。

- 新增 string-escape（constant.character.escape.viper）并让 4 条字符串规则 include
- 单行字符串 end 由引号改为「引号或行尾」，即使写错也不会把作用域拖到下一行

packages/vscode-vipeye/syntaxes/viper.tmLanguage.json

@@ -78,6 +78,9 @@
                     "begin": "\"\"\"",
                     "end": "\"\"\"",
                     "patterns": [
+                        {
+                            "include": "#string-escape"
+                        },
                         {
                             "include": "#fstring-interpolation"
                         }
@@ -88,6 +91,9 @@
                     "begin": "'''",
                     "end": "'''",
                     "patterns": [
+                        {
+                            "include": "#string-escape"
+                        },
                         {
                             "include": "#fstring-interpolation"
                         }
@@ -96,8 +102,11 @@
                 {
                     "name": "string.quoted.double.viper",
                     "begin": "\"",
-                    "end": "\"",
+                    "end": "\"|$",
                     "patterns": [
+                        {
+                            "include": "#string-escape"
+                        },
                         {
                             "include": "#fstring-interpolation"
                         }
@@ -106,8 +115,11 @@
                 {
                     "name": "string.quoted.single.viper",
                     "begin": "'",
-                    "end": "'",
+                    "end": "'|$",
                     "patterns": [
+                        {
+                            "include": "#string-escape"
+                        },
                         {
                             "include": "#fstring-interpolation"
                         }
@@ -115,6 +127,14 @@
                 }
             ]
         },
+        "string-escape": {
+            "patterns": [
+                {
+                    "name": "constant.character.escape.viper",
+                    "match": "\\\\."
+                }
+            ]
+        },
         "fstring-interpolation": {
             "patterns": [
                 {