style(代码配色): printf 里的 %d、%.2f 和 Python f-string 的 { } 有了自己的颜色；Python 的 from / as / with 和 import 一个颜色，跟 VS Code 一样

lezer 把整个字符串当一个词，占位符另外扫一遍（shared/formatPlaceholder.ts），编辑器挂装饰、
静态代码拆 span，用同一份正则。Python 解析器补了几条 styleTags，编辑器和静态代码共用。
CodeEditor.vue 原来自己抄了一份语言选择，改成用 languageExtension。

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/web/src/shared/components/CodeEditor.vue

@@ -1,7 +1,4 @@
 <script lang="ts" setup>
-import { cpp } from "@codemirror/lang-cpp"
-import { python } from "@codemirror/lang-python"
-import { sql, SQLite } from "@codemirror/lang-sql"
 import { bracketMatching } from "@codemirror/language"
 import CodeMirror from "./CodeMirror.vue"
 import type { Extension } from "@codemirror/state"
@@ -10,6 +7,7 @@ import type { LANGUAGE } from "utils/types"
 import { darkCodeTheme, lightCodeTheme } from "../themes/codeTheme"
 import { styleTheme } from "shared/extensions/baseTheme"
 import { enhanceCompletion } from "shared/extensions/autocompletion"
+import { languageExtension } from "shared/extensions/language"
 
 interface Props {
   language?: LANGUAGE
@@ -33,10 +31,7 @@ const code = defineModel<string>("value")
 
 const isDark = useDark()
 
-const langExtension = computed(() => {
-  if (language === "SQL") return sql({ dialect: SQLite, upperCaseKeywords: true })
-  return language === "Python" ? python() : cpp()
-})
+const langExtension = computed(() => languageExtension(language))
 
 const extensions = computed(() => [
   styleTheme,