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/airouter/v1/bin/anthropic-compat-wrapper.sh

@@ -0,0 +1,10 @@
+#!/bin/bash
+# Anthropic-compat wrapper for airouter harness (Phase 9 ESO-managed secrets)
+# Reads airouter credentials from /run/agent/secrets/airouter/ and passes them
+# as env vars to the underlying Claude runner.
+set -euo pipefail
+
+exec env \
+  ANTHROPIC_AUTH_TOKEN="$(cat /run/agent/secrets/airouter/auth_token)" \
+  ANTHROPIC_BASE_URL="$(cat /run/agent/secrets/airouter/base_url)" \
+  claude "$@"