chore(platform-infra): commit parallel proxy updates

docs/reference/pk01.md

@@ -14,6 +14,33 @@ docker ps --format 'table {{.Names}}\t{{.Image}}\t{{.Status}}'
 SH
 ```
 
+When the PK01 provider-gateway channel is offline, operators may use the ignored break-glass SSH source `.env/PK01_ssh.txt`. The file format is two lines: line 1 is the SSH target such as `ubuntu@<host>`, line 2 is the password. Do not print the second line, commit it, copy it into issue comments, or pass it through commands that echo typed input. Prefer an ephemeral `SSH_ASKPASS` wrapper so OpenSSH can handle `keyboard-interactive` or password prompts without exposing the value:
+
+```bash
+tmp=$(mktemp -d /tmp/pk01-askpass.XXXXXX)
+chmod 700 "$tmp"
+cat >"$tmp/askpass.sh" <<'SH'
+#!/bin/sh
+printf '%s\n' "$PK01_SSH_PASS"
+SH
+chmod 700 "$tmp/askpass.sh"
+
+PK01_SSH_PASS="$(sed -n '2p' .env/PK01_ssh.txt)" \
+SSH_ASKPASS="$tmp/askpass.sh" \
+SSH_ASKPASS_REQUIRE=force \
+DISPLAY=none \
+setsid -w ssh \
+  -o StrictHostKeyChecking=accept-new \
+  -o ConnectTimeout=8 \
+  -o PreferredAuthentications=keyboard-interactive,password,publickey \
+  "$(sed -n '1p' .env/PK01_ssh.txt)" \
+  'hostname; date -Is'
+
+rm -rf "$tmp"
+```
+
+This fallback is for bounded host diagnostics or node-local recovery only. After restoring `unidesk-provider-gateway-pk01`, return to `trans PK01 ...` and `platform-infra ... --target PK01` as the operating truth.
+
 Before closing an operation, verify both the provider channel and host workload state:
 
 ```bash
@@ -36,7 +63,9 @@ PK01 currently uses a direct Docker provider-gateway deployment rather than a fu
 | Env file | `/home/ubuntu/.unidesk/state/provider-pk01/provider.env` | Contains provider token and must not be printed, copied into docs, or committed. |
 | Host SSH key | `/home/ubuntu/.unidesk/host-ssh-pk01/id_ed25519` | Mounted read-only at `/run/host-ssh`; public key is authorized for `ubuntu`. |
 | Logs | `/home/ubuntu/.unidesk/logs/provider-pk01` | Node-local runtime logs, not a Git source of truth. |
-| Egress proxy | `127.0.0.1:18789` | Loopback only; never expose as a public endpoint. |
+| Host SSH target | `root@host.docker.internal:22` | `trans PK01 ...` is expected to land as root for host/systemd operations. |
+| Provider-gateway egress proxy | `127.0.0.1:18789` | Provider maintenance tunnel only; do not bind Sub2API upstream accounts to this endpoint. |
+| Host proxy HTTP endpoint | `127.0.0.1:10809` | PK01 host proxy endpoint for Sub2API account proxy binding, declared by `config/platform-infra/host-proxy.yaml#targets.PK01`. |
 
 Long-term provider-gateway upgrades should converge to the standard `provider.upgrade mode=schedule` flow described in `docs/reference/provider-gateway.md`. If PK01 is still on the direct Docker bootstrap path, do not rebuild the gateway synchronously through the gateway's own `trans PK01` session. Use a detached node-local job or first move PK01 to the standard attach/upgrade bundle.
 
@@ -68,7 +97,9 @@ If one public service fails while other services still work, restore the missing
 
 In this mode, public ports `80` and `443` belong to Caddy. The existing `pikanode` container must be bound to a loopback HTTP port and used only as the apex PikaPython/PikaNode upstream. Public platform routes must be read from their owning YAML. For the current Sub2API PK01 host-Docker target, `api.pikapython.com` uses `publicExposure.mode=pk01-local` and API traffic follows `client -> PK01 Caddy -> 127.0.0.1:<YAML local upstream port> -> PK01 host-Docker Sub2API`. For k3s external-active targets, the route may instead be `client -> PK01 Caddy -> PK01 frps remote port -> target frpc -> target Sub2API`. Neither path may pass through pikanode or a master-server reverse proxy.
 
-Caddy binary installation is also YAML-controlled. If `publicExposure.pk01.caddyDownloadProxyUrl` is set, PK01 Caddy downloads must use that proxy URL; the PK01 loopback provider egress proxy is the preferred source. A slow or failing Caddy download should first be treated as missing proxy use, not as a reason to keep retrying a naked GitHub release download.
+Caddy binary installation is also YAML-controlled. If `publicExposure.pk01.caddyDownloadProxyUrl` is set, PK01 Caddy downloads must use that proxy URL. Sub2API account-level proxy binding must use the PK01 host proxy HTTP endpoint, not the provider-gateway egress proxy.
+
+PK01's account-level host proxy is a status-only Hysteria client connected to the NC01-local `../vpn-server` deployment. The durable declaration is `config/platform-infra/host-proxy.yaml#targets.PK01`, and protected/manual Sub2API account bindings should reference it through `config/platform-infra/sub2api-codex-pool.yaml` `manualAccounts.bindingSources.*.hostProxyRef`. Do not replace it with `127.0.0.1:18789`; verify it with `bun scripts/cli.ts platform-infra egress-proxy host status --target PK01` and then validate the Sub2API account/user request path.
 
 The public certificate depends on DNS. The `api.pikapython.com` record must resolve to the YAML-declared PK01 public address before Caddy can complete ACME issuance. If the DNS record is absent or stale, local probes such as PK01 loopback app health checks, loopback Caddy `--resolve` checks, or target-specific FRP remote-port checks can prove parts of the data path, but final `https://api.pikapython.com` validation remains blocked until DNS is corrected.