fix(harnesses): migrate to ESO secrets_required form, mirror agent-runtimes

The CRS-served harnesses still carried `secrets_files: [{encrypted: true}]`
which now hard-fails on H-SECRET-1 ("SOPS-encrypted secrets_files entries
are no longer permitted") in the dispatcher's harness validator. Sync the
8 provider harnesses with the agent-runtimes copies: same `secrets_required`
shape, same `init.sh` (ESO-mounted file paths), same `bin/` wrappers.

Use bare `account_ref: "<provider>"` (not `<provider>.cp:cp` — that
scope-kind isn't valid per SR-DISP-1-FIELD).

Provider key names follow the per-provider schema as emitted by the CP
provisioner: minimax/airouter/z-ai → api_key; gitea-https/gitea-admin →
{token,base_url,username}; gitea-ssh* → {host,private_key}.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

harnesses/contexts/gitea-ssh-accelerators/v1/harness.yaml

@@ -18,7 +18,8 @@ ssh_hosts:
 scripts:
   init: "./init.sh"
 
-secrets_files:
-  - source: ./ssh-key.sops.env
-    target: /opt/harness/secrets/gitea-ssh-accelerators/ssh-key.sops.env
-    encrypted: true
+secrets_required:
+  - name: gitea-ssh-accelerators
+    account_ref: "gitea-ssh-accelerators"
+    mount_path: /run/agent/secrets/gitea-ssh-accelerators
+    mode: "0400"

harnesses/contexts/gitea-ssh-accelerators/v1/init.sh

@@ -1,29 +1,21 @@
 #!/bin/bash
+# gitea-ssh-accelerators init: copy the ESO-mounted SSH key to the path the
+# harness-init `~/.ssh/config` expects (`IdentityFile /home/agent/.ssh/gitea-oreillyit-nz-accelerators`).
+#
+# Per H-SECRET-4: NO `export` of credentials. (The earlier draft set
+# `GIT_SSH_COMMAND` here — a path, not a credential — but that export dies
+# with the subshell and the harness-init's SSH config is the load-bearing
+# path anyway.)
 set -euo pipefail
 
-# Extract SSH private key from decrypted env file for the accelerators identity.
-# The meta-init script generates ~/.ssh/config with
-# IdentityFile /home/agent/.ssh/gitea-oreillyit-nz-accelerators
-# matching the ssh_hosts alias in harness.yaml.
+SSH_KEY_SRC="/run/agent/secrets/gitea-ssh-accelerators/id_ed25519"
+SSH_KEY_DST="/home/agent/.ssh/gitea-oreillyit-nz-accelerators"
 
-SSH_KEY_FILE="/home/agent/.ssh/gitea-oreillyit-nz-accelerators"
-
-for env_file in /opt/harness/secrets/gitea-ssh-accelerators/*.decrypted.env /opt/harness/secrets/gitea-ssh-accelerators/*.env; do
-    [ -f "$env_file" ] || continue
-    while IFS='=' read -r key value; do
-        [[ "$key" =~ ^[[:space:]]*# ]] && continue
-        [[ -z "$key" ]] && continue
-        if [ "$key" = "GITEA_SSH_KEY" ]; then
-            mkdir -p /home/agent/.ssh
-            echo "$value" | base64 -d > "$SSH_KEY_FILE"
-            chmod 600 "$SSH_KEY_FILE"
-            chown agent:agent "$SSH_KEY_FILE"
-            echo "SSH key written to $SSH_KEY_FILE"
-            break 2
-        fi
-    done < "$env_file"
-done
-
-if [ ! -f "$SSH_KEY_FILE" ]; then
-    echo "WARNING: GITEA_SSH_KEY not found in any env file under /opt/harness/secrets/gitea-ssh-accelerators/"
+if [ ! -r "$SSH_KEY_SRC" ]; then
+    echo "ERROR: SSH key not found at $SSH_KEY_SRC — ESO ExternalSecret not Ready?" >&2
+    exit 1
 fi
+
+mkdir -p /home/agent/.ssh
+install -m 0600 -o agent -g agent "$SSH_KEY_SRC" "$SSH_KEY_DST"
+echo "gitea-ssh-accelerators: SSH key staged at $SSH_KEY_DST (0600 agent:agent)"