Initial commit: Matrix stack (Synapse + Synapse-Admin + Element Web) behind Traefik

Fully dockerized deployment with automatic Let's Encrypt certificates via
Traefik's static file provider (no docker.sock needed), bind-mounted data
folders instead of named volumes, and domain/secrets kept out of git via
.env + rendered templates.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,19 @@
+# Real secrets / domain — never commit
+.env
+CREDENTIALS.txt
+
+# Traefik ACME storage (contains private keys + certificates)
+traefik/acme/acme.json
+
+# Runtime data (bind-mounted host folders, not named volumes)
+postgres/data/*
+!postgres/data/.gitkeep
+
+synapse/data/*
+!synapse/data/.gitkeep
+
+# Rendered configs (contain the real domain) — templates are tracked instead
+element/config/config.json
+synapse-admin/config/config.json
+wellknown/html/well-known-matrix-client.json
+traefik/dynamic/routes.yml