PBI-55: .env.example descriptive push placeholders + README push-integration section

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.env.example

@@ -5,5 +5,7 @@ DATABASE_URL="postgresql://user:pass@host:5432/dbname"
 SCRUM4ME_TOKEN=""
 
 # Internal push endpoint (main-app) for web-push notifications
-INTERNAL_PUSH_URL=""
+# Set to the main-app /api/internal/push/send URL; leave empty to disable push (feature-gated).
-INTERNAL_PUSH_SECRET=""
+INTERNAL_PUSH_URL="https://scrum4me.example.com/api/internal/push/send"
+# Shared secret (≥32 chars) — must match INTERNAL_PUSH_SECRET in the main-app env.
+INTERNAL_PUSH_SECRET="<generate-with: openssl rand -hex 32>"

README.md

@@ -296,6 +296,10 @@ Minimale agent-prompt (geen CLAUDE.md-context nodig):
 
 > *Pak de volgende job uit de Scrum4Me-queue.*
 
+## Web-push integration
+
+When `INTERNAL_PUSH_URL` and `INTERNAL_PUSH_SECRET` are set, the MCP server fires a fire-and-forget push notification to the main-app's internal endpoint (`/api/internal/push/send`) on two events: when `ask_user_question` creates a new question (tag `claude-q-<id>`), and when `update_job_status` transitions a job to `done` or `failed` (tag `job-<id>`). Both calls are wrapped in a 5 s `AbortController` timeout and a `try/catch` so a push failure never interrupts the tool response. Omitting the env vars disables the feature entirely. The `INTERNAL_PUSH_SECRET` value must match the one configured in the main-app; generate a fresh secret with `openssl rand -hex 32`.
+
 ## Schema sync
 
 The Prisma schema is the source of truth in the upstream Scrum4Me