Add full shell, replaceable Omics adapter and bilingual interaction

Implement approved specification #32 and tickets #33-#37. Keep host authentication server-verified and pin session interaction language. Compile scoped base selectors for browser compatibility and retain full gutters during CSS pruning.

frontend/src/viewers/mermaid.ts

@@ -1,10 +1,19 @@
-let _initialized = false;
+let initializedTheme: "light" | "dark" | undefined;
+let rendering: Promise<unknown> = Promise.resolve();
 
-export async function renderMermaid(def: string): Promise<string> {
+export function renderMermaid(def: string, theme: "light" | "dark" = "light"): Promise<string> {
+  // Mermaid configuration is global: serialize renders so a theme change cannot
+  // recolor another diagram midway through its asynchronous rendering.
+  const result = rendering.then(() => renderDiagram(def, theme));
+  rendering = result.catch(() => undefined);
+  return result;
+}
+
+async function renderDiagram(def: string, theme: "light" | "dark"): Promise<string> {
   const mermaid = (await import("mermaid")).default;
-  if (!_initialized) {
-    mermaid.initialize({ startOnLoad: false, theme: "default" });
-    _initialized = true;
+  if (initializedTheme !== theme) {
+    mermaid.initialize({ startOnLoad: false, theme: theme === "dark" ? "dark" : "default" });
+    initializedTheme = theme;
   }
   const id = `mermaid-${Math.random().toString(36).slice(2)}`;
   const container = document.createElement("div");