feat(mana-auth): wire Glitchtip/Sentry error tracking via shared-error-tracking

First server-side error-tracking integration. Pattern mirrors the
client-side one in apps/mana/apps/web/src/hooks.client.ts:

- pull @mana/shared-error-tracking into mana-auth's deps (workspace pkg
  with @sentry/node + a no-op fallback when GLITCHTIP_DSN is unset)
- call initErrorTracking() at the top of services/mana-auth/src/index.ts
  before the rest of the module body executes — this lets Sentry hook
  uncaughtException / unhandledRejection before any Hono handlers register
- wrap app.onError so non-HTTPException throws also flow into
  captureException with path/method/query context. HTTPExceptions are
  intentional 4xx/422 and stay out of the issue list (otherwise every
  401 from a stale session would page somebody at 3am)
- compose: pass GLITCHTIP_DSN_MANA_PLATFORM through as GLITCHTIP_DSN per
  service so each container's events get tagged with serverName='mana-auth'

DSN itself isn't in the repo; lives in .env.macmini on the Mac Mini and
is referenced from the Glitchtip credentials doc.

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

docker-compose.macmini.yml

@@ -290,6 +290,10 @@ services:
       # returns 503 GRANT_NOT_CONFIGURED (graceful degrade).
       MANA_AI_PUBLIC_KEY_PEM: ${MANA_AI_PUBLIC_KEY_PEM:-}
       MANA_NOTIFY_URL: http://mana-notify:3013
+      # Glitchtip error reporting (Phase 2d, 2026-05-07). DSN is the
+      # mana-platform project on glitchtip.mana.how; per-service env so
+      # each service ends up tagged with its serverName.
+      GLITCHTIP_DSN: ${GLITCHTIP_DSN_MANA_PLATFORM:-}
       MAX_DAILY_SIGNUPS: ${MAX_DAILY_SIGNUPS:-0}
       # Must be a superset of TRUSTED_ORIGINS in
       # services/mana-auth/src/auth/better-auth.config.ts.