feat: add app code

- journal domain package
- httpserver package
- html templates
- main.go in root dir

templates/deleted-entry.html

@@ -0,0 +1,16 @@
+{{ template "layout.html" . }}
+
+{{ define "title" }}Entry deleted{{ end }}
+
+{{ define "content" }}
+<style>
+  p {
+    font-size: 1.2rem;
+    line-height: 1.5;
+    text-align: center;
+  }
+</style>
+<main class="container">
+   <p>Entry has been deleted.</p>
+</main>
+{{ end }}