bug: v0.0.88 gateway rejects enable_bind_mounts in TOML config despite docs listing it as valid

[aknochow]

Description

After upgrading from v0.0.86 to v0.0.88, the gateway rejects enable_bind_mounts in gateway.toml:

Error: configuration error: invalid [openshell.drivers.podman] table:
unknown field `enable_bind_mounts`, expected one of `socket_path`,
`default_image`, `image_pull_policy`, `grpc_endpoint`, `gateway_port`,
`sandbox_ssh_socket_path`, `network_name`, `host_gateway_ip`,
`stop_timeout_secs`, `supervisor_image`, `guest_tls_ca`, `guest_tls_cert`,
`guest_tls_key`, `sandbox_pids_limit`

The gateway crashes on startup — no compute driver loads. Sandbox creation with --provider hangs indefinitely (sandbox reaches Ready but the create command never returns).

Documentation vs binary mismatch

The v0.0.88 gateway-config reference lists enable_bind_mounts as a valid [openshell.drivers.podman] field. The compiled v0.0.88 binary does not accept it.

This appears to be the same pattern as #2339 (sandbox_child_nproc_limit merged but absent from release binaries).

Downgrade blocked by DB migration

Downgrading to v0.0.86 fails because v0.0.88 applied migration 6:

Error: execution error: migration error: migration 6 was previously applied
but is missing in the resolved migrations

Workaround: delete the gateway database at ~/.local/state/openshell/gateway/openshell.db and restart. This loses provider config (must recreate providers).

Steps to reproduce

1. Install v0.0.86, configure enable_bind_mounts = true in gateway.toml (works)
2. Upgrade to v0.0.88
3. Gateway fails to start with "unknown field" error
4. All sandbox creation with --provider hangs

Environment

• macOS (Apple Silicon)
• Podman Desktop 5.8.2
• OpenShell v0.0.88 (Homebrew)
• Gateway TOML config with enable_bind_mounts = true

Workaround

Remove enable_bind_mounts from gateway.toml, or downgrade to v0.0.86 after deleting ~/.local/state/openshell/gateway/openshell.db.

[krishicks]

I was not able to reproduce this on v0.0.88 or on main.