Chore(sentry): skip Sentry init in dev runs

A local pnpm dev with a DSN in .env reported every half-finished edit
against the production projects. The frontend gate now also checks
import.meta.env.DEV; the backend bootstrap skips init under
SENTRY_ENVIRONMENT=development, mirroring the cron check-in rule.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

api/AGENTS.md

@@ -60,7 +60,9 @@ currently `dns-resolvers.js`, the country-annotated resolver list behind
   Root-level `sentry-instrument.js` (loaded via `node --import` *before*
   express, so ESM loader hooks can auto-instrument route tracing) does the
   init; `backend-server.js` attaches `setupExpressErrorHandler` after the
-  routes. No `SENTRY_DSN_BACKEND` → `@sentry/node` never loads. Handlers
+  routes. No `SENTRY_DSN_BACKEND` → `@sentry/node` never loads;
+  `SENTRY_ENVIRONMENT=development` skips the init, so a local run reports
+  nothing (same rule the cron check-ins already follow). Handlers
   never import Sentry or capture manually: uncaught throws and 5xx traces
   are automatic; caught failures stay on the logger — a hook in
   `common/logger.js` mirrors warn+ to Sentry Logs and elevates error+ to

frontend/AGENTS.md

@@ -76,7 +76,9 @@ replaces the map, and Home clears it on unmount — shortcuts are home-route onl
 ### Error monitoring (Sentry) is env-gated and invisible to app code
 
 No `VITE_SENTRY_DSN_FRONTEND` → no Sentry code in the bundle at all
-(build-time-gated dynamic import, like `firebase-init.js`). Rules:
+(build-time-gated dynamic import, like `firebase-init.js`). The same gate in
+`main.js` skips the load under `import.meta.env.DEV`, so a `pnpm dev` run
+reports nothing even with a DSN in `.env`. Rules:
 
 - **Never import `@sentry/vue` in app code** — a static import drags the SDK
   into the main bundle. All config lives in `sentry-init.js`.

frontend/main.js

@@ -66,16 +66,18 @@ const store = useMainStore(pinia);
 app.use(i18n);
 app.use(router);
 
-// Sentry — build-time env gate: without the DSN the chunk neither ships nor
-// loads. The SDK chunk stays OFF the boot critical path: it loads after
-// mount (see the mount chain's finally below) so it never competes with the
-// locale pack the first render waits on. Until init, a tiny buffer catches
-// uncaught errors / rejections — and any of them triggers an immediate
-// load, so a boot that never reaches mount still reports. Perf data
-// survives the late init (buffered observers, backdated pageload span).
+// Sentry — build-time env gate: without the DSN, or in a dev server run, the
+// chunk neither ships nor loads (local runs would otherwise report every
+// experiment against the production project). The SDK chunk stays OFF the
+// boot critical path: it loads after mount (see the mount chain's finally
+// below) so it never competes with the locale pack the first render waits
+// on. Until init, a tiny buffer catches uncaught errors / rejections — and
+// any of them triggers an immediate load, so a boot that never reaches mount
+// still reports. Perf data survives the late init (buffered observers,
+// backdated pageload span).
 const earlyErrors = [];
 let loadSentry = () => {};
-if (import.meta.env.VITE_SENTRY_DSN_FRONTEND) {
+if (import.meta.env.VITE_SENTRY_DSN_FRONTEND && !import.meta.env.DEV) {
     const onEarlyError = (event) => {
         earlyErrors.push(event);
         loadSentry();

sentry-instrument.js

@@ -5,14 +5,18 @@
 //
 // Gated on SENTRY_DSN_BACKEND, same philosophy as the frontend: when the env
 // var is unset this module does nothing and @sentry/node is never even
-// loaded. backend-server.js attaches the matching Express error handler.
+// loaded. SENTRY_ENVIRONMENT=development skips init too, so a local run never
+// reports. backend-server.js attaches the matching Express error handler.
 import dotenv from 'dotenv';
 
 import { scrubBreadcrumb, scrubEventRequest, scrubSpan } from './common/sentry-scrub.js';
 
 dotenv.config({ quiet: true });
 
-if (process.env.SENTRY_DSN_BACKEND) {
+// SENTRY_ENVIRONMENT=development (a local `pnpm dev` machine) skips init:
+// experiments in progress are not production signal, same rule as the cron
+// check-ins in common/sentry-cron.js.
+if (process.env.SENTRY_DSN_BACKEND && process.env.SENTRY_ENVIRONMENT !== 'development') {
     const Sentry = await import('@sentry/node');
     Sentry.init({
         dsn: process.env.SENTRY_DSN_BACKEND,