feat: add RegisterResult component, ESLint config, and vue.config.js for project setup

- Created a new RegisterResult.vue component for displaying registration success.
- Added ESLint configuration for unit tests in the tests directory.
- Implemented vue.config.js for webpack configuration, including theme color support and proxy settings for development.

frontend_vue/.gitattributes

@@ -0,0 +1,11 @@
+public/* linguist-vendored
+
+# Automatically normalize line endings (to LF) for all text-based files.
+* text=auto eol=lf
+
+# Declare files that will always have CRLF line endings on checkout.
+*.{cmd,[cC][mM][dD]} text eol=crlf
+*.{bat,[bB][aA][tT]} text eol=crlf
+
+# Denote all files that are truly binary and should not be modified.
+*.{ico,png,jpg,jpeg,gif,webp,svg,woff,woff2} binary