Add `--tunnel-service` option to `fedify lookup` and `fedify inbox` commands

[dahlia]

Currently, the fedify tunnel command provides a -s/--service option to choose the tunneling service (localhost.run, serveo.net, or pinggy.io). However, two other commands that use tunneling internally don't have this option.

The fedify lookup command uses tunneling when --authorized-fetch is specified, and fedify inbox uses tunneling by default unless -T/--no-tunnel is provided. In both cases, users cannot select which tunneling service to use.

Rationale

This inconsistency is problematic when the default tunneling service is unavailable or has poor connectivity. Users should be able to switch to alternative services just like they can with fedify tunnel.

Proposed change

Add a --tunnel-service option to fedify lookup and fedify inbox commands. For consistency, also add --tunnel-service as an alias to the existing -s/--service option in fedify tunnel (keeping both for backward compatibility).

For fedify lookup, the option would only apply when --authorized-fetch is used. For fedify inbox, it would apply when tunneling is enabled (no -T/--no-tunnel flag).

The new option should only have a long-form (no short abbreviation) since suitable short-form options are already taken (-t for --traverse, -S for --suppress-errors). Since tunneling service selection isn't frequently changed, requiring the full option name is acceptable.

[dahlia]

The fedify relay command also uses tunneling by default (can be disabled with -T/--no-tunnel), so it should also get the --tunnel-service option for consistency.

[dahlia]

To ensure --tunnel-service is only valid when tunneling is enabled (i.e., when -T/--no-tunnel is not specified), we can use Optique's or() combinator to create mutually exclusive option groups:

or(
  object({
    tunnel: map(flag("-T", "--no-tunnel"), () => false as const),
  }),
  object({
    tunnel: constant(true),
    tunnelService: optional(option("--tunnel-service", string())),
  }),
)

This pattern ensures:

• When -T/--no-tunnel is specified: tunneling is disabled, --tunnel-service is not available
• When -T is not specified: tunneling is enabled by default, --tunnel-service can optionally be used
• When both -T and --tunnel-service are specified together: parsing error (prevents invalid combinations at parse time rather than runtime validation)

This should be applied consistently to fedify lookup, fedify inbox, and fedify relay commands.

References:

• Optique or() combinator
• Optique map() modifier