Update programs to the new Leo 4.x syntax

[eranrund]

This is the minimal set of changes required to get the programs to compile with the most recent leo version and test using the new devnode.

While the previous (leo 3.5) version of this code was audited, technically this one wasn't - but since no logic changes should've taken place, and the bytecode wasn't audited, this might be acceptable for use in future projects.

Either way, I think having this is a good thing since it can be used as a developer reference for how to easily build a JS SDK-based test suite.

[Copilot]

Pull request overview

This PR updates the Leo programs and test tooling for Leo 4.x/devnode compatibility, including syntax migration from async transitions/functions to fn/Final patterns and SDK/devnode test adjustments.

Changes:

• Migrates multisig and token registry Leo source to Leo 4.0.2 syntax.
• Updates test dependencies and execution transaction construction for devnode.
• Refreshes README setup instructions for Leo 4.0.2 and devnode usage.

Reviewed changes

Copilot reviewed 11 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
programs/multisig_core/src/main.leo	Migrates core multisig program functions/finalization helpers to Leo 4 syntax.
programs/multisig_core/program.json	Updates Leo version metadata to 4.0.2.
programs/multisig_wallet/src/main.leo	Migrates wallet program calls, futures, and helper finalizers to Leo 4 syntax.
programs/multisig_wallet/program.json	Updates Leo version metadata to 4.0.2.
token_registry/src/main.leo	Migrates local token registry implementation to Leo 4 syntax.
token_registry/build/main.aleo	Updates generated Aleo output for the migrated token registry.
token_registry/build/program.json	Adds Leo version metadata.
tests/lib/aleo-test-utils.js	Switches skipped-proof execution to devnode transaction builder.
tests/multisig.test.js	Updates expected SDK/devnode failure text.
tests/package.json / tests/package-lock.json	Switches SDK dependency from local file path to published 0.10.5 package.
README.md	Updates development/setup documentation for Leo 4.0.2 and devnode.

Files not reviewed (1)

• tests/package-lock.json: Language not supported

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