refactor: Migrate to ESM and Vite for modern build

Updates package.json and index.html to use ES Modules and Vite for development and building. This includes migrating dependencies and removing old build scripts and testing configurations.

Also, simplifies the Gemini API key handling by directly using environment variables and refactors the Gemini response schema for clearer field definitions. Updates React component imports to use ESM paths for better maintainability.

.gitignore

@@ -4,26 +4,85 @@ logs
 npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
-pnpm-debug.log*
-lerna-debug.log*
 
-# Python
-__pycache__/
-*.py[cod]
-*.pytest_cache/
+# Runtime data
+pids
+*.pid
+*.seed
+*.pid.lock
 
-node_modules
-dist
-dist-ssr
-*.local
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
 
-# Editor directories and files
-.vscode/*
-!.vscode/extensions.json
-.idea
+# Coverage directory used by tools like istanbul
+coverage
+
+# nyc test coverage
+.nyc_output
+
+# Grunt intermediate storage (http://gruntjs.com/creating-plugins#storing-task-files)
+.grunt
+
+# Bower dependency directory (https://bower.io/)
+bower_components
+
+# node-waf configuration
+.lock-wscript
+
+# Compiled binary addons (https://nodejs.org/api/addons.html)
+build/Release
+
+# Dependency directories
+node_modules/
+jspm_packages/
+
+# TypeScript v1 declaration files
+typings/
+
+# Optional npm cache directory
+.npm
+
+# Optional eslint cache
+.eslintcache
+
+# Optional REPL history
+.node_repl_history
+
+# Output of 'npm pack'
+*.tgz
+
+# Yarn Integrity file
+.yarn-integrity
+
+# dotenv environment variables file
+.env
+.env.test
+
+# parcel-bundler cache (https://parceljs.org/)
+.cache
+
+# next.js build output
+.next
+
+# nuxt.js build output
+.nuxt
+
+# vuepress build output
+.vuepress/dist
+
+# Serverless directories
+.serverless/
+
+# FuseBox cache
+.fusebox/
+
+# DynamoDB Local files
+.dynamodb/
+
+# OS metadata
 .DS_Store
-*.suo
-*.ntvs*
-*.njsproj
-*.sln
-*.sw?
+Thumbs.db
+
+# Dist folder
+dist/
+dist-ssr/