feat: home page template with carousel, news, about, services, team sections

- Extends base.html, uses shared image macro for resize_image
- Refactored img shortcode to forward to macros/image.html (DRY)
- News pulled via get_page from content/news.md
- Notfall section skipped (was unpublished in grav)
- Map call commented out until shortcode lands in Task 20

templates/shortcodes/img.html

@@ -1,16 +1,8 @@
-{# Image shortcode with width-based resize and lazy loading.
+{# Image shortcode for use inside Markdown content.
+   Forwards to the shared image macro so we have one source of truth.
    Usage in markdown:
      {{ img(src="team/Olli.jpg", width=400, alt="Dr. Riemann") }}
-     {{ img(src="carousel/page1.jpg", width=1920, alt="Praxis") }}
-   Class is optional, e.g. class="float-right". #}
-
-{%- set source_path = "static/images/" ~ src -%}
-{%- set resized = resize_image(path=source_path, width=width, op="fit_width", quality=85) -%}
-<img
-  src="{{ resized.url }}"
-  width="{{ resized.width }}"
-  height="{{ resized.height }}"
-  alt="{{ alt | default(value="") }}"
-  {%- if class %} class="{{ class }}"{% endif %}
-  loading="lazy"
->
+     {{ img(src="services/HV.jpg", width=600, alt="...", class="float-right") }}
+#}
+{%- import "macros/image.html" as image -%}
+{{ image::render(src=src, width=width, alt=alt | default(value=""), class=class | default(value="")) }}