consolidate: fold openbureau (+ rapport, dossier) into about; drop it as a standalone nav destination

about now lists cv.md, openbureau.md, rapport.md, dossier.md side by side. the standalone /openbureau/ page, its layout, and its home-menu entry are gone; internal links repointed to /about/. also switch the info-panel text to justified (with hyphenation, per earlier request) instead of ragged-right.

hugo.toml

@@ -34,10 +34,6 @@ enableRobotsTXT = true
         name = "about"
         pageRef = "/about"
         weight = 2
-      [[languages.en.menu.main]]
-        name = "openbureau"
-        pageRef = "/openbureau"
-        weight = 4
 
   [languages.de]
     locale = "de_CH"
@@ -54,10 +50,6 @@ enableRobotsTXT = true
         name = "about"
         pageRef = "/about"
         weight = 2
-      [[languages.de.menu.main]]
-        name = "openbureau"
-        pageRef = "/openbureau"
-        weight = 4
 
 [markup]
   [markup.goldmark.renderer]