feat: add app code

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

templates/new-entry.html

@@ -0,0 +1,74 @@
+{{ template "layout.html" . }}
+
+{{ define "title" }}New entry{{ end }}
+
+{{ define "content" }}
+<style>
+  form {
+    display: flex;
+    flex-direction: column;
+    /* max-width: 600px; */
+    margin: 0 auto;
+  }
+  form input,
+  form textarea {
+    font-size: 1rem;
+    width: calc(100% - 1rem);
+  }
+  form input[type="date"] {
+    padding: 0.5rem;
+    margin-bottom: 1rem;
+    border-radius: 0.5rem;
+    border: 1px solid #ccc;
+  }
+  form input[type="text"] {
+    padding: 0.5rem;
+    margin-bottom: 1rem;
+    border-radius: 0.5rem;
+    border: 1px solid #ccc;
+  }
+  form textarea {
+    padding: 0.5rem;
+    margin-bottom: 1rem;
+    border-radius: 0.5rem;
+    border: 1px solid #ccc;
+    resize: none;
+    height: 24rem;
+  }
+  /* form button {
+    font-size: 1rem;
+    padding: 0.5rem 1rem;
+    border-radius: 0.5rem;
+    border: none;
+    background-color: #000;
+    color: white;
+    cursor: pointer;
+    width: 100%;
+  }
+  form button:hover {
+    background-color: #333;
+  } */
+</style>
+<script>
+  function saveEntry(event) {
+    event.preventDefault();
+    document.getElementById('new-entry').submit();
+  }
+  function clearForm(event) {
+    event.preventDefault();
+    document.getElementById('new-entry').reset();
+  }
+</script>
+<main class="container">
+  <h1>New entry</h1>
+  <hr />
+  <form id="new-entry" action="/entry/new" method="POST">
+    <input type="text" name="title" placeholder="Title" required>
+    <input type="date" name="date" value="{{ .Today }}" required>
+    <textarea name="content" placeholder="Content" rows="12" required></textarea>
+    <div>
+      [<a href="#" onclick="saveEntry(event)">Save</a>]&nbsp;[<a href="#" onclick="clearForm(event)">Clear</a>]
+    </div>
+  </form>
+</main>
+{{ end }}