feat: add site header (#2)

* tests: setup initial infra for end to end tests

* tests: rework end to end host

* tests: remove need for bang operator

* tests: correct header component tests

* docs: add README.md to blog directory with instructions on setting up local dev environment with and without docker

* docs: update non-developer run command

* feat: finish layout of header

* feat: add favicon

* tests: setup test coverage

* chore: update workflow with missing playwright step

* chore: add install command

test/Blog.Tests/Unit/Header.spec.razor

@@ -0,0 +1,32 @@
+@inherits Bunit.TestContext
+
+@code
+{
+  [Test]
+  public void Header_WhenRendered_ItShouldContainSiteTitle()
+  {
+    var cut = Render(@<Header />);
+
+    var heading = cut.Find("h1");
+
+    heading.MarkupMatches(@<h1>journal</h1>);
+  }
+
+  [Test]
+  public void Header_WhenRendered_ItShouldContainAuthorInfo()
+  {
+    var cut = Render(@<Header />);
+
+    var author = cut.Find(".author-container > span");
+
+    author.MarkupMatches(@<span>by</span>);
+  }
+
+  [Test]
+  public void Header_WhenRendered_ItShouldContainAuthorImage()
+  {
+    var cut = Render(@<Header />);
+    var image = cut.Find("img[alt='Stevan Freeborn']");
+    image.Should().NotBeNull();
+  }
+}