Support inline call-type parameter syntax for Sudo, Utility.batch, and Proxy wrappers

Problem

Pallets that wrap other calls — Sudo.sudo, Utility.batch/batchAll, Proxy.proxy — currently require the inner call to be passed as verbose JSON enum syntax:

dot tx Sudo.sudo \
  '{"type":"ParasSudoWrapper","value":{"type":"sudo_establish_hrmp_channel","value":{"sender":1000,"recipient":1004,"max_capacity":8,"max_message_size":10000}}}' \
  --from alice

This pattern is repeated throughout the scripting workflows. For example in scripts/setup-pusd.sh:

run_tx "Create foreign PUSD asset on People Chain" Sudo.sudo \
  '{"type":"Assets","value":{"type":"force_create","value":{"id":'"$PUSD_FOREIGN_ASSET_ID"',"owner":"'"$ALICE_SS58"'","is_sufficient":true,"min_balance":10}}}' \
  --from "$SUDO_ACCOUNT" --chain "$PEOPLE_CHAIN"

And in scripts/setup-hrmp-channels.sh:

run_tx "$label" Sudo.sudo \
  '{"type":"ParasSudoWrapper","value":{"type":"sudo_establish_hrmp_channel","value":{"sender":'"$sender"',"recipient":'"$recipient"',"max_capacity":'"$HRMP_MAX_CAPACITY"',"max_message_size":'"$HRMP_MAX_MESSAGE_SIZE"'}}}' \
  --from "$SUDO_ACCOUNT" --chain "$RELAY_CHAIN"

The triple-nested {"type":"...","value":{"type":"...","value":{...}}} is error-prone, hard to read, and painful with shell variable interpolation.

Proposed Solution

Support two additional input formats alongside the existing JSON syntax:

1. Inline Pallet.call notation

For single-Call wrappers (Sudo.sudo, Proxy.proxy), detect when a positional argument matches Pallet.call syntax and consume subsequent positional args as parameters for the inner call:

# Before
dot tx Sudo.sudo \
  '{"type":"ParasSudoWrapper","value":{"type":"sudo_establish_hrmp_channel","value":{"sender":1000,"recipient":1004,"max_capacity":8,"max_message_size":10000}}}' \
  --from alice

# After
dot tx Sudo.sudo ParasSudoWrapper.sudo_establish_hrmp_channel 1000 1004 8 10000 \
  --from alice

# Before
dot tx Sudo.sudo \
  '{"type":"Assets","value":{"type":"force_create","value":{"id":1984,"owner":"5GrwvaE...","is_sufficient":true,"min_balance":10}}}' \
  --from alice --chain ws://localhost:9910

# After
dot tx Sudo.sudo Assets.force_create 1984 "5GrwvaE..." true 10 \
  --from alice --chain ws://localhost:9910

For Vec<Call> wrappers (Utility.batch, Utility.batchAll), use a separator (e.g. -- or ,) between calls:

dot tx Utility.batchAll \
  Balances.transfer_keep_alive "5FHneW46..." 1000000000000 , \
  Balances.transfer_keep_alive "5FLSigC9..." 2000000000000 \
  --from alice

2. Hex-encoded SCALE call data

Accept a 0x-prefixed hex string as a pre-encoded call:

dot tx Sudo.sudo 0x<scale-encoded-call-data> --from alice

This is useful for cross-tool workflows where call data is generated externally.

Detection & Parsing Approach

• When to activate: The metadata lookup for the parameter will have RuntimeCall as its type ID (or equivalent). Use the metadata to detect when a parameter expects a Call type.
• Inline notation: When the arg matches Word.word and the expected type is a Call enum, resolve the pallet variant and call variant from metadata, then use cursor-based consumption of subsequent positional args to fill the inner call's fields (same logic already used by parseCallArgs for top-level calls).
• Hex-encoded: When the arg starts with 0x and the expected type is a Call, pass the raw bytes through.
• JSON: Existing {"type":"...","value":{...}} syntax continues to work unchanged (backwards compatible).

Scope

• Single-level nesting (Sudo wrapping one call, Utility.batch wrapping a flat list) covers the vast majority of real-world usage.
• Deep nesting (e.g. Sudo.sudo Utility.batchAll Balances.transfer ...) would be nice-to-have but is not required for the initial implementation.

Backwards Compatibility

The existing JSON object syntax ('{"type":"...","value":{...}}') continues to work. The new formats are detected by shape — Pallet.call pattern or 0x prefix — and only apply when the expected parameter type is a Call.

Start by locating the existing parseCallArgs logic and the metadata lookup for parameters typed as RuntimeCall. Implement and verify inline Pallet.call arguments, 0x-encoded call data, and separated Utility.batch calls while preserving the existing JSON syntax; done means the Sudo, Proxy, batch, and batchAll examples work.