[go] rewrite interface{} to any

[qmuntal]

interface{} is a relic form the past. Rewrite it to any using gofmt -w -r 'interface{} -> any' ..

[Copilot]

Pull request overview

This PR modernizes the Go codebase by replacing all instances of the legacy interface{} type with the modern any alias, which was introduced in Go 1.18. The changes were made using gofmt -w -r 'interface{} -> any' ., ensuring consistency across the codebase.

Changes:

• Replaced all occurrences of interface{} with any in type declarations, function signatures, and variable declarations
• Updated code comments to reflect the new type nomenclature
• Cleaned up trailing whitespace in README.md

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
go/types.go	Updated struct field types and type aliases from interface{} to any
go/session.go	Updated function parameter and variable types from interface{} to any
go/jsonrpc.go	Updated JSON-RPC struct types and function signatures from interface{} to any
go/generated_session_events.go	Updated generated code struct fields and utility function signatures from interface{} to any
go/e2e/session_test.go	Updated test code type declarations from interface{} to any
go/definetool_test.go	Updated test assertions and type casts from interface{} to any
go/definetool.go	Updated function return types and comments from interface{} to any
go/client_test.go	Updated test parameter types from interface{} to any
go/client.go	Updated function signatures, variable declarations, and map types from interface{} to any
go/README.md	Updated code examples from interface{} to any and removed trailing whitespace

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[friggeri]

@qmuntal I merged your other PRs, this one has a merge conflict