feat(web-tanstack): Sentry instrumentation via @sentry/node + @sentry/react + R38 PII test

Adds initSentryServerNode + initSentryClientReact to core-shared
(Vite/non-Next variants of the existing init helpers — same R31/R32/R33
posture, R34/R35/R37 replay defaults). Extends no-sentry.ts to mock
@sentry/node + @sentry/react. Wires the web-tanstack server/client
instrumentation entry hooks and adds the R38 PII test.

Spec deviation: web-tanstack has no vite.config.ts yet (placeholder app
per its package.json). The @sentry/vite-plugin dep is added but unused
until the TanStack Start build is wired in a later plan. A minimal
src/vite-env.d.ts shims ImportMetaEnv for the client entry until the
full Vite types land.

@sentry/node and @sentry/react are added to core-shared as optional
peerDependencies so feature packages don't transitively pull them in;
they're also devDependencies of core-shared for typecheck/test runs.

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

apps/web-tanstack/src/vite-env.d.ts

@@ -0,0 +1,11 @@
+// Minimal Vite-style env typing for the instrumentation-client entry.
+// When the full TanStack Start / Vite build is wired in a later plan,
+// replace this with `/// <reference types="vite/client" />`.
+interface ImportMetaEnv {
+  readonly VITE_WEB_TANSTACK_SENTRY_DSN?: string;
+  readonly VITE_GIT_COMMIT_SHA?: string;
+}
+
+interface ImportMeta {
+  readonly env: ImportMetaEnv;
+}