feat: deprecate JRPC V1

[lwin-kyaw]

Motivation and Context

Jira Link:

Description

How has this been tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project. (run lint)
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.
• My code requires a db migration.

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Note

Low Risk
Primarily adds @deprecated annotations and documentation with no runtime behavior changes; the only functional change is a TypeScript-level generic return type on propagateToMutableRequest, plus lockfile metadata churn.

Overview
Marks the JRPC V1 engine, middleware types, provider helpers, and postMessage stream utilities as deprecated, with JSDoc pointers to the preferred V2 equivalents (e.g. JRPCEngineV2, JRPCMiddlewareV2, createEngineStreamV2, providerFromEngineV2).

Updates propagateToMutableRequest in v2/compatibility-utils to support a generic return type (and adds tests for the new typing behavior), and includes lockfile-only cleanup removing peer: true metadata entries.

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[chaitanyapotti]

rename ReturnType since it shadows ts generic