AGENTS.md: mandate self-healing, boot-persistent quadlet units for every container

A bare compose container dies silently at reboot (rootless Podman has no
boot-time auto-start; 'restart: unless-stopped' does not survive shutdown's
explicit stop). Rule established by the 2026-08-26 Dankclaw reboot, which
left Caddy down and Pi-hole crash-looping on a sysctl conflict.

AGENTS.md

@@ -130,6 +130,43 @@ graph LR
     G --> H[Per-service health check]
 ```
 
+## Boot Persistence & Self-Healing (MANDATORY)
+
+Every Podman container governed by this project that is successfully deployed
+and proven working MUST have a self-healing, boot-persistent Quadlet unit. A
+container that runs only from `compose.yaml` (or a manual `podman run`) dies
+silently at reboot: rootless Podman does not auto-start bare containers, and
+`restart: unless-stopped` does not survive the explicit stop that shutdown
+performs. Do not report such a service as "up" without its unit.
+
+Each container's unit must provide:
+
+- **Boot persistence** — `[Install] WantedBy=default.target`, installed to
+  `~/.config/containers/systemd/<name>.container` (generating
+  `<name>.service`) and enabled in the user manager
+  (`systemctl --user enable <name>.service`). Linger must be on for the deploy
+  user (`loginctl show-user dank -p Linger` → `Linger=yes`) so user units start
+  at boot with no login session.
+- **Self-healing** — `[Service] Restart=always` (or `Restart=on-failure`) with
+  a short `RestartSec`, so a crash or OOM brings the container back without
+  operator action. Add a quadlet health check where the service has one.
+- **Repo provenance** — the `.container` file lives in this repo
+  (`dankclaw/<svc>/quadlet/` or `dankserver/<svc>/quadlet/`), is installed by
+  the service-scoped deployer, and is covered by the quadlet test seam. The
+  host-side unit is generated state; the repo file is the source of truth.
+
+Verification before a service is declared deployed:
+`systemctl --user is-enabled <name>.service` → `enabled`,
+`systemctl --user is-active <name>.service` → `active`, and the container
+answers its health check. A running container with no unit is a gap: write the
+unit, test it, deploy it.
+
+Incident that established this rule (2026-08-26, Dankclaw reboot): Caddy ran
+for weeks as a bare compose container and never came back after reboot; the
+Pi-hole unit existed but crash-looped on a sysctl conflict (a later-sorted
+drop-in reset `net.ipv4.ip_unprivileged_port_start` to 80), taking LAN DNS
+down with it.
+
 ## Testing
 
 Tests are mandatory before commit. `bats` must be installed on the
@@ -409,7 +446,7 @@ two hosts, one Caddy, and one Gitea. One repo keeps them in one history.
 | Editing a compose/Caddyfile/serve script | **Work through git** — fetch, commit, edit, test, push, pull, deploy. Never edit on the remote directly. |
 | Config exists only on remote | **Pull it into the repo first** — commit the fetched version (redacted) before making changes. |
 | Unstaged local changes | **Commit or discard** — check `git status` before starting work. Ask the user if unsure. |
-| Deploying a committed change | **Run `scripts/deploy.sh <target>`** — it pushes, pulls with fast-forward-only, plans changed paths, dispatches selected services, and checks their health. See [docs/LLM/deployment.md](docs/LLM/deployment.md). |
+| Deploying a committed change | **Run `scripts/deploy.sh <target>`** — it pushes, pulls with fast-forward-only, plans changed paths, dispatches selected services, and checks their health. See [docs/LLM/deployment.md](docs/LLM/deployment.md). | | Container without a Quadlet unit | **Give it one** — self-healing, boot-persistent `.container` unit via git (see Boot Persistence & Self-Healing). |
 | Benchmarking | **Stop the service first**, restart, verify health. See the Benchmarking Policy above. |
 | Deleting a file | **Move it to trash** — `.AGENTTRASH/` (in-repo) or `~/.AGENTTRASH/YYYYMMDD-topic`. Never `rm`. |
 | Tests exist | **Run them** — verify tests pass after every change. Do not commit failing tests. |