feat(developer): VSCode plugin for building

- initial checkin

Fixes: #12756

developer/src/keyman-vscode-plugin/.gitignore

@@ -0,0 +1,5 @@
+out
+dist
+node_modules
+.vscode-test/
+*.vsix

developer/src/keyman-vscode-plugin/.vscode-test.mjs

@@ -0,0 +1,5 @@
+import { defineConfig } from '@vscode/test-cli';
+
+export default defineConfig({
+	files: 'out/test/**/*.test.js',
+});

developer/src/keyman-vscode-plugin/.vscodeignore

@@ -0,0 +1,11 @@
+.vscode/**
+.vscode-test/**
+src/**
+.gitignore
+.yarnrc
+vsc-extension-quickstart.md
+**/tsconfig.json
+**/eslint.config.mjs
+**/*.map
+**/*.ts
+**/.vscode-test.*

developer/src/keyman-vscode-plugin/eslint.config.mjs

@@ -0,0 +1,28 @@
+import typescriptEslint from "@typescript-eslint/eslint-plugin";
+import tsParser from "@typescript-eslint/parser";
+
+export default [{
+    files: ["**/*.ts"],
+}, {
+    plugins: {
+        "@typescript-eslint": typescriptEslint,
+    },
+
+    languageOptions: {
+        parser: tsParser,
+        ecmaVersion: 2022,
+        sourceType: "module",
+    },
+
+    rules: {
+        "@typescript-eslint/naming-convention": ["warn", {
+            selector: "import",
+            format: ["camelCase", "PascalCase"],
+        }],
+
+        curly: "warn",
+        eqeqeq: "warn",
+        "no-throw-literal": "warn",
+        semi: "warn",
+    },
+}];