docs: reflect live koopa state (inventory + exchange-ansible)

Capture what is actually running on host koopa: podman names/ports,
Caddy vhosts, and hernani paths. Authoritative snapshot:
host/overview/LIVE.md.

Rename docs to live container taler-hacktivism-exchange-ansible
(not the short taler-exchange-hacktivism label). Add public-only
mirror of ~/ansible-taler-exchange deploy helpers (no secrets.yml).

configs/taler-exchange-ansible/README.md

@@ -0,0 +1,33 @@
+# Exchange on koopa — Ansible-managed container
+
+**Live state reflected from host koopa** (not a full upstream clone of ansible-taler-exchange).
+
+| Item | Live on koopa |
+|------|----------------|
+| Container name | **`taler-hacktivism-exchange-ansible`** |
+| Image | `localhost/taler-hacktivism-exchange-ansible:landing` (build tag `:base`) |
+| Ports | **9011** (API), **9014** (landing/intro) |
+| Site | `https://exchange.hacktivism.ch` |
+| Tree | `/home/hernani/ansible-taler-exchange/` |
+| Secrets | `inventories/host_vars/.../secrets.yml` — **not** in admin-log |
+
+## Files here (mirrors / excerpts)
+
+| File | Role |
+|------|------|
+| `run-container-koopa.sh` | Build image, run systemd container `--name taler-hacktivism-exchange-ansible` |
+| `deploy-hacktivism-goa.sh` | `ansible-playbook` limit that host + public/secrets vars |
+| `Containerfile` | Debian + systemd base for the container |
+| `public.yml` | Non-secret host_vars for hacktivism GOA |
+| `inventories-default.snippet` | Inventory lines for the koopa container host |
+
+## Ops
+
+```bash
+cd ~/ansible-taler-exchange
+./run-container-koopa.sh          # recreate container if needed
+./deploy-hacktivism-goa.sh        # apply ansible (needs secrets.yml + vault)
+podman ps --filter name=taler-hacktivism-exchange-ansible
+```
+
+Full host inventory of all services: **`host/overview/LIVE.md`**.