fix(build): keep the server logger out of client bundles

The production webpack build failed with UnhandledSchemeError: client
components imported @/lib/logger, which binds pino, AsyncLocalStorage
(node:async_hooks), node:crypto and node:fs — and validates server env on
import. The UI fixture aliased those modules, so the harness and tests
never hit it.

- add src/lib/browser-log.ts: browser-safe logger with the same interface;
  errors are forwarded to /api/diagnostics/errors via reportBrowserError
- guard src/lib/logger.ts with server-only and drop its now-dead browser
  branches
- switch the 11 client components/hooks to @/lib/browser-log

Verified with the Dockerfile's production build (pnpm run build) and the
full vitest suite.

src/app/admin/sounds/sounds-client.tsx

@@ -45,8 +45,8 @@ import {
 import { Textarea } from "@/components/ui/textarea";
 import { useServerAction } from "@/hooks/use-server-action";
 import { adminFetch } from "@/lib/admin-fetch";
+import { logger } from "@/lib/browser-log";
 import { invalidateSongPickerCache } from "@/lib/client-cache/song-picker-cache";
-import { logger } from "@/lib/logger";
 import { parseTraxChannels } from "@/lib/trax-format";
 import { TraxPlayer } from "./trax-player";
 

src/app/admin/sounds/trax-player.tsx

@@ -19,7 +19,7 @@ import { Loader2, Play, Square } from "lucide-react";
 import { useCallback, useEffect, useRef, useState } from "react";
 import { toast } from "sonner";
 import { Button } from "@/components/ui/button";
-import { logger } from "@/lib/logger";
+import { logger } from "@/lib/browser-log";
 import { TRAX_TICK_SECONDS, type TraxChannel } from "@/lib/trax-format";
 
 const TICK_SECONDS = TRAX_TICK_SECONDS;