Consolidate Sentry config into shared package; fix inconsistencies

Introduces @trails-cool/sentry-config with three helpers that encode
the common Sentry.init options:
- nodeSentryConfig(appContext) for the two HTTP servers
- browserSentryConfig(appContext, env) for the Journal client
- mobileSentryConfig(__DEV__) for the React Native app
- drop404s beforeSend for servers

Also fixes three inconsistencies found in the audit:
- Planner server was missing sendDefaultPii: false (IPs could leak)
- Planner entry.server.tsx didn't call Sentry.captureException on SSR
  render errors; Journal's SSR did
- Sentry.init location now matches across apps (both in server.ts;
  Journal previously had it in app/entry.server.tsx, which meant init
  ran lazily on first request rather than at server startup)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/mobile/lib/sentry.ts

@@ -1,22 +1,13 @@
 import * as Sentry from "@sentry/react-native";
+import { mobileSentryConfig } from "@trails-cool/sentry-config";
 
 const SENTRY_DSN = "https://af50ac7aea803216adbe21e9dd4b896b@o4509530546634752.ingest.de.sentry.io/4511209742532688";
 
 export function initSentry() {
-  const enabled = !__DEV__;
   Sentry.init({
     dsn: SENTRY_DSN,
-    tracesSampleRate: __DEV__ ? 0 : 1.0,
-    enabled,
-    sendDefaultPii: false,
-    // Session Replay is not installed; document the intent explicitly.
-    replaysSessionSampleRate: 0,
-    replaysOnErrorSampleRate: 0,
+    ...mobileSentryConfig(__DEV__),
   });
-
-  if (!enabled) {
-    console.debug("[sentry] mobile init inert in dev; would send to Sentry in production");
-  }
 }
 
 export { Sentry };

apps/mobile/package.json

@@ -38,6 +38,7 @@
     "@trails-cool/gpx": "workspace:*",
     "@trails-cool/i18n": "workspace:*",
     "@trails-cool/map-core": "workspace:*",
+    "@trails-cool/sentry-config": "workspace:*",
     "@trails-cool/types": "workspace:*",
     "expo": "~55.0.15",
     "expo-constants": "~55.0.14",