The /_tuwunel namespace carries Tuwunel's ad-hoc routes (server_version,
local_user_count) and its native OpenID Connect provider endpoints
(/_tuwunel/oidc/...), which a reverse proxy must route for OIDC login
to work. Add public (enabled by default, like the client API) and
internal Traefik label groups.

Tuwunel serves the Synapse administration API under /_synapse/admin,
but the role only routed /_matrix, so admin dashboards and moderation
bots could not reach it. Add public and internal Traefik label groups
mirroring the matrix-synapse role, and enable them automatically when
Ketesa, Element Admin, or Draupnir is installed.

Files in this role were ported from matrix-continuwuity (which carries
2025 attribution), so the year range should reflect that the underlying
content predates 2026.

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/5200.

Tuwunel is a Matrix homeserver maintained by the matrix-construct
organisation. See https://matrix-construct.github.io/tuwunel/.

The rendered TOML emits only keys exposed as Ansible variables; the
rest fall back to tuwunel's upstream defaults. Anything not surfaced
can be set via the TUWUNEL_* env extension or by overriding the
template path.

Popular features Tuwunel adds variables for:

- OAuth2/OIDC identity providers (a list of `[[global.identity_provider]]`
  blocks; brand-aware defaults for Google, GitHub, Keycloak, MAS, etc)
- LDAP and JWT authentication
- Media storage providers (native local and S3 with multipart upload)
- RocksDB tuning (compression, direct_io, parallelism, online backups)
- Native TLS dual-protocol mode
- Blurhashing, Sentry crash reporting

Auto-wired from existing playbook globals: well-known client URL,
TURN/coturn, MatrixRTC LiveKit URL, federation.

The `tuwunel-migrate-from-conduwuit` tag performs a binary-swap
migration. Migration from any other Conduit derivative is unsupported
and would corrupt the database.

Signed-off-by: Jason Volk <jason@zemos.net>