prototype unified administration page layouts

docs/adr/0020-unify-administration-pages-and-use-namespaced-routes.md

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+# Unify administration pages and use namespaced routes
+
+status: accepted
+
+Workspace and Pi management will become full Administration Pages alongside Evidence, Memory and
+Database, using one shared Administrative Page Family. The Embedded Thoth Shell will identify the
+active Administration Surface through a namespaced browser route, `thoth_route=administration/<surface>`,
+so links remain reloadable and support Back/Forward without requiring new host-portal server routes.
+Transient form values and secrets stay outside the route; destructive confirmations may remain
+short-lived dialogs because they are actions, not page containers.
+
+We considered React-only state, path-based routes and hash routes. React-only state loses refresh and
+deep-link behavior, path routes require a host catch-all route that does not yet exist in Omics Portal,
+and hash routes can conflict with host-page fragments. A namespaced query route preserves the current
+same-document integration boundary while leaving room for a future path adapter.