Web UI: Jarl logo and wordmark

Add the logo, a Viking jarl drawn like a woodcut whose spear-pointed crown
holds a DNS tree. It is generated by scripts/logo.py, which mirrors the
left half so the figure is exactly symmetrical, as logo.svg (white on a
Nordic-blue disc) and logo-white.svg. It links home in the header, sits on
the login page and is the favicon.

The login page shows an angular "JARL" wordmark drawn as SVG paths over a
rule with a "DNS" node, coloured from the theme. The header's "Jarl" uses
a self-hosted Cinzel Bold subset (SIL OFL); jarld serves .woff2 as
font/woff2.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/web/static/assets/brand.js

@@ -0,0 +1,39 @@
+// The "JARL" wordmark for the login page: angular Norse-style letters
+// drawn as paths (no font needed), over a rule with DNS nodes. The letters
+// use the text color and the rule the accent color, so it follows the
+// theme.
+const NS = "http://www.w3.org/2000/svg";
+
+function el(tag, attrs, ...children) {
+  const e = document.createElementNS(NS, tag);
+  for (const [k, v] of Object.entries(attrs || {})) e.setAttribute(k, v);
+  for (const c of children) e.append(c instanceof Node ? c : document.createTextNode(c));
+  return e;
+}
+
+// Letters on a 100-unit cap height; counters are cut with evenodd.
+const letters = [
+  // J: a heavy stem whose foot hooks back into a barb
+  { x: 0, d: "M14 0 H48 V10 H42 V80 L31 100 H5 L0 93 L19 84 H24 V10 H14 Z" },
+  // A: peaked top, flaring legs, a diamond for a counter
+  { x: 60, d: "M35 0 L46 10 L64 90 L70 100 H50 L44 76 L35 62 L26 76 L20 100 H0 L6 90 L24 10 Z M35 26 L41 40 L35 54 L29 40 Z" },
+  // R: squared bowl with cut corners, a long kicked leg
+  { x: 142, d: "M0 0 H48 L60 12 V40 L50 50 L66 100 H46 L34 60 H18 V100 H0 Z M18 14 H41 L46 19 V35 L41 46 H18 Z" },
+  // L: the base ends in an upswept spike
+  { x: 220, d: "M0 0 H18 V84 H40 L58 70 L54 100 H0 Z" },
+];
+
+export function wordmark() {
+  const letterG = el("g", { fill: "currentColor", "fill-rule": "evenodd" },
+    ...letters.map((l) => el("path", { d: l.d, transform: `translate(${l.x} 0)` })));
+  // The rule: tapered lines, two nodes and a "DNS" node in the middle.
+  const rule = el("g", { class: "wordmark-rule", transform: "translate(0 118)" },
+    el("path", { d: "M2 18 L98 15.6 V20.4 Z M278 18 L182 15.6 V20.4 Z", class: "fill" }),
+    el("circle", { cx: 106, cy: 18, r: 4.6, class: "line" }),
+    el("path", { d: "M110.6 18 H122 M158 18 H169.4", class: "line" }),
+    el("circle", { cx: 140, cy: 18, r: 17, class: "line" }),
+    el("circle", { cx: 174, cy: 18, r: 4.6, class: "line" }),
+    el("text", { x: 140, y: 22.5, "text-anchor": "middle", class: "dns" }, "DNS"));
+  return el("svg", { class: "wordmark", viewBox: "-4 -4 288 162", role: "img", "aria-label": "Jarl" },
+    el("title", null, "Jarl"), letterG, rule);
+}