fix: remove duplicate brand CSS fetch step in docs workflow

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Fieldnote-Echo

.github/workflows/docs.yml

@@ -33,10 +33,6 @@ jobs:
         run: |
           curl -sL https://raw.githubusercontent.com/Project-Navi/brand/main/docs/stylesheets/navi.css \
             -o docs/stylesheets/navi.css
-      - name: Fetch brand CSS
-        run: |
-          curl -sL https://raw.githubusercontent.com/Project-Navi/brand/main/docs/stylesheets/navi.css \
-            -o docs/stylesheets/navi.css
       - name: Build site
         run: uv run zensical build
       - name: Strip internal docs from build