feat(branding): embed slohmaier logo on cover + running page header

- branding/: light + dark logo SVG sources and 1600x452 PNG renders
- build_word_template.py: replace [LOGO] placeholder with add_picture
  on cover (7 cm wide, right-aligned) plus a 2.8 cm logo as a second
  paragraph in the running page header so derived pandoc-generated
  templates inherit the branding on every page

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

branding/logo-doc-dark.svg

@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  slohmaier.com Dokument-Logo (Dark) — Braille-Icon + Wortmarke
+  mit Accent-Border. Für Word/PDF-Letterheads (280–320 px Breite).
+-->
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 780 220" width="780" height="220"
+     role="img" aria-label="slohmaier">
+  <defs>
+    <radialGradient id="bgGradient" cx="50%" cy="50%" r="50%">
+      <stop offset="0%"   stop-color="#2a3f5f"/>
+      <stop offset="100%" stop-color="#1a2330"/>
+    </radialGradient>
+    <radialGradient id="dotGradient" cx="50%" cy="50%" r="50%">
+      <stop offset="0%"   stop-color="#ffffff" stop-opacity="1"/>
+      <stop offset="100%" stop-color="#c8dcff" stop-opacity="0.6"/>
+    </radialGradient>
+    <linearGradient id="wmDark" x1="0%" y1="0%" x2="100%" y2="0%">
+      <stop offset="0%"   stop-color="#D4A574"/>
+      <stop offset="100%" stop-color="#5BA5D6"/>
+    </linearGradient>
+  </defs>
+
+  <rect x="10" y="10" width="760" height="200" rx="10" ry="10"
+        fill="#21273a" stroke="#D4A574" stroke-width="3"/>
+
+  <!-- Icon (2E) — 160×160 bei (30,30), scale 160/512 = 0.3125 -->
+  <g transform="translate(30 30) scale(0.3125)">
+    <rect x="18" y="18" width="476" height="476" rx="92" ry="92" fill="#ffffff"/>
+    <rect x="30" y="30" width="452" height="452" rx="80" ry="80" fill="url(#bgGradient)"/>
+    <circle cx="94"  cy="256" r="36" fill="url(#dotGradient)"/>
+    <circle cx="94"  cy="371" r="36" fill="url(#dotGradient)"/>
+    <circle cx="184" cy="141" r="36" fill="url(#dotGradient)"/>
+    <circle cx="329" cy="141" r="36" fill="url(#dotGradient)"/>
+    <circle cx="329" cy="256" r="36" fill="url(#dotGradient)"/>
+    <circle cx="329" cy="371" r="36" fill="url(#dotGradient)"/>
+  </g>
+
+  <text x="220" y="148" font-family="Aptos, Inter, Helvetica Neue, Arial, sans-serif"
+        font-size="110" font-weight="700" letter-spacing="-2">
+    <tspan fill="url(#wmDark)">sl</tspan><tspan fill="#eaedf3">ohmaier</tspan>
+  </text>
+</svg>

branding/logo-doc-light.svg

@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  slohmaier.com Dokument-Logo (Light) — Braille-Icon + Wortmarke
+  mit Accent-Border. Für Word/PDF-Letterheads (280–320 px Breite).
+-->
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 780 220" width="780" height="220"
+     role="img" aria-label="slohmaier">
+  <defs>
+    <radialGradient id="bgGradient" cx="50%" cy="50%" r="50%">
+      <stop offset="0%"   stop-color="#2a3f5f"/>
+      <stop offset="100%" stop-color="#1a2330"/>
+    </radialGradient>
+    <radialGradient id="dotGradient" cx="50%" cy="50%" r="50%">
+      <stop offset="0%"   stop-color="#ffffff" stop-opacity="1"/>
+      <stop offset="100%" stop-color="#c8dcff" stop-opacity="0.6"/>
+    </radialGradient>
+    <linearGradient id="wmLight" x1="0%" y1="0%" x2="100%" y2="0%">
+      <stop offset="0%"   stop-color="#5BA5D6"/>
+      <stop offset="100%" stop-color="#D4A574"/>
+    </linearGradient>
+  </defs>
+
+  <rect x="10" y="10" width="760" height="200" rx="10" ry="10"
+        fill="#ffffff" stroke="#5BA5D6" stroke-width="3"/>
+
+  <!-- Icon (2E) — 160×160 bei (30,30), scale 160/512 = 0.3125 -->
+  <g transform="translate(30 30) scale(0.3125)">
+    <rect x="18" y="18" width="476" height="476" rx="92" ry="92" fill="#ffffff"/>
+    <rect x="30" y="30" width="452" height="452" rx="80" ry="80" fill="url(#bgGradient)"/>
+    <circle cx="94"  cy="256" r="36" fill="url(#dotGradient)"/>
+    <circle cx="94"  cy="371" r="36" fill="url(#dotGradient)"/>
+    <circle cx="184" cy="141" r="36" fill="url(#dotGradient)"/>
+    <circle cx="329" cy="141" r="36" fill="url(#dotGradient)"/>
+    <circle cx="329" cy="256" r="36" fill="url(#dotGradient)"/>
+    <circle cx="329" cy="371" r="36" fill="url(#dotGradient)"/>
+  </g>
+
+  <text x="220" y="148" font-family="Aptos, Inter, Helvetica Neue, Arial, sans-serif"
+        font-size="110" font-weight="700" letter-spacing="-2">
+    <tspan fill="url(#wmLight)">sl</tspan><tspan fill="#282728">ohmaier</tspan>
+  </text>
+</svg>