[Tests] Improve TOML codec coverage with encodeToml tests

[gonzaloriestra]

Added comprehensive unit tests for encodeToml in packages/cli-kit/src/public/node/toml/codec.test.ts to improve coverage and prevent regressions, validating simple key-value pairs and structured nested objects/blocks.

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PR created automatically by Jules for task 13157068248553567506 started by @gonzaloriestra

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