feat(ui): init banner + dashboard shield favicon

cmd/agent-gate/init_cmd.go

@@ -40,6 +40,14 @@ func initCmd() *cobra.Command {
 			caDir := filepath.Join(configDir, "ca")
 
 			interactive := !nonInteractive && isInteractive()
+
+			// Banner: show for any non-quiet run. Suppressed for
+			// --print-config (stdout is structured) and --quiet. Goes
+			// to stderr so it never contaminates a piped --print-config.
+			if !quiet && !printConfig {
+				v, _, _ := buildInfo()
+				initwizard.PrintBanner(cmd.ErrOrStderr(), v)
+			}
 			var prompter initwizard.Prompter
 			if interactive {
 				prompter = initwizard.HuhPrompter{}

internal/dashboard/server.go

@@ -40,6 +40,12 @@ func NewServer(opts Options) http.Handler {
 	staticFS, _ := fs.Sub(assets, "static")
 	mux.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.FS(staticFS))))
 
+	// Some browsers still request /favicon.ico even with <link rel="icon">.
+	// Send them to the SVG instead of letting it 404.
+	mux.HandleFunc("/favicon.ico", func(w http.ResponseWriter, r *http.Request) {
+		http.Redirect(w, r, "/static/favicon.svg", http.StatusFound)
+	})
+
 	// Routes.
 	mux.HandleFunc("/", handleSessionsList(opts, r))
 	mux.HandleFunc("/sessions/", handleSessionDetail(opts, r))

internal/dashboard/server_test.go

@@ -60,6 +60,33 @@ func TestServerRendersFullPageOnGetRoot(t *testing.T) {
 	assert.Contains(t, bodyStr, "<html")
 	assert.Contains(t, bodyStr, "agent-gate")
 	assert.Contains(t, bodyStr, `src="/static/htmx.min.js"`)
+	assert.Contains(t, bodyStr, `href="/static/favicon.svg"`)
+}
+
+func TestServerServesFavicon(t *testing.T) {
+	srv := httptest.NewServer(NewServer(freshOpts(t)))
+	defer srv.Close()
+
+	resp, err := http.Get(srv.URL + "/static/favicon.svg")
+	require.NoError(t, err)
+	defer resp.Body.Close()
+	assert.Equal(t, 200, resp.StatusCode)
+	body, _ := io.ReadAll(resp.Body)
+	assert.Contains(t, string(body), "<svg")
+}
+
+func TestServerRedirectsFaviconIco(t *testing.T) {
+	srv := httptest.NewServer(NewServer(freshOpts(t)))
+	defer srv.Close()
+
+	client := &http.Client{CheckRedirect: func(req *http.Request, via []*http.Request) error {
+		return http.ErrUseLastResponse
+	}}
+	resp, err := client.Get(srv.URL + "/favicon.ico")
+	require.NoError(t, err)
+	defer resp.Body.Close()
+	assert.Equal(t, http.StatusFound, resp.StatusCode)
+	assert.Equal(t, "/static/favicon.svg", resp.Header.Get("Location"))
 }
 
 func TestServerRefusesNonLoopbackBind(t *testing.T) {

internal/dashboard/templates/base.html

@@ -4,6 +4,7 @@
   <meta charset="utf-8">
   <meta name="viewport" content="width=device-width, initial-scale=1">
   <title>agent-gate</title>
+  <link rel="icon" type="image/svg+xml" href="/static/favicon.svg">
   <link rel="preconnect" href="https://fonts.googleapis.com">
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=Plus+Jakarta+Sans:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap">

internal/initwizard/banner.go

@@ -0,0 +1,44 @@
+package initwizard
+
+import (
+	"fmt"
+	"io"
+
+	"github.com/charmbracelet/lipgloss"
+)
+
+// bannerArt is the wordmark printed at the top of `agent-gate init`.
+// Block characters render at any reasonable terminal width (~42 cols)
+// and survive copy/paste better than figlet output. Indentation is
+// added by PrintBanner so lipgloss styling doesn't strip leading
+// whitespace from line 1.
+var bannerArt = []string{
+	"▄▀█ █▀▀ █▀▀ █▄ █ ▀█▀     █▀▀ ▄▀█ ▀█▀ █▀▀",
+	"█▀█ █▄█ ██▄ █ ▀█  █      █▄█ █▀█  █  ██▄",
+}
+
+const (
+	bannerIndent  = "   "
+	bannerTagline = "◆ local traffic audit gate"
+)
+
+// PrintBanner writes the agent-gate wordmark + tagline to w. Caller decides
+// whether to suppress it (e.g. --quiet, --print-config).
+//
+// version is shown after the tagline; pass "" to omit. Color is applied via
+// lipgloss; lipgloss auto-degrades on TERM=dumb / non-TTY writers.
+func PrintBanner(w io.Writer, version string) {
+	accent := lipgloss.NewStyle().Foreground(lipgloss.Color("#0E7C5A")).Bold(true)
+	tagline := lipgloss.NewStyle().Foreground(lipgloss.Color("#0E7C5A")).Faint(true)
+
+	fmt.Fprintln(w)
+	for _, line := range bannerArt {
+		fmt.Fprintln(w, bannerIndent+accent.Render(line))
+	}
+	line := bannerTagline
+	if version != "" {
+		line = fmt.Sprintf("%s · %s", bannerTagline, version)
+	}
+	fmt.Fprintln(w, bannerIndent+tagline.Render(line))
+	fmt.Fprintln(w)
+}

internal/initwizard/banner_test.go

@@ -0,0 +1,40 @@
+package initwizard
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+)
+
+func TestPrintBannerContainsWordmarkAndTagline(t *testing.T) {
+	var buf bytes.Buffer
+	PrintBanner(&buf, "")
+	got := buf.String()
+
+	for _, line := range bannerArt {
+		if !strings.Contains(got, line) {
+			t.Errorf("banner missing wordmark line %q\nfull output:\n%s", line, got)
+		}
+	}
+	if !strings.Contains(got, bannerTagline) {
+		t.Errorf("banner missing tagline %q\nfull output:\n%s", bannerTagline, got)
+	}
+}
+
+func TestPrintBannerIncludesVersionWhenProvided(t *testing.T) {
+	var buf bytes.Buffer
+	PrintBanner(&buf, "v0.3.1")
+	got := buf.String()
+
+	if !strings.Contains(got, "v0.3.1") {
+		t.Errorf("banner did not include version; output:\n%s", got)
+	}
+}
+
+func TestPrintBannerOmitsVersionWhenEmpty(t *testing.T) {
+	var buf bytes.Buffer
+	PrintBanner(&buf, "")
+	if strings.Contains(buf.String(), " · ") {
+		t.Errorf("banner should not include separator when version is empty; output:\n%s", buf.String())
+	}
+}