fix: logger to read from env map instead of std::env (#2235)

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> [!IMPORTANT]
> Logger configuration now reads from an environment map, with updated
`ConfigValue` and `From` trait implementations, and new tests added.
> 
>   - **Behavior**:
> - Logger configuration now reads from an environment map instead of
directly from `std::env`.
> - Updates `ConfigValue` trait implementations for `LogLevelConfig`,
`JsonModeConfig`, `ColorModeConfig`, `LspConfig`, and
`MaxMessageLengthConfig` to support reading from a map.
> - Modifies `From` trait implementations for these configs to
prioritize map values over `std::env`.
>   - **Tests**:
> - Adds tests in `logger.rs` to verify configuration reading from
environment maps and handling of invalid values.
> - Tests include `test_set_from_env_updates_config`,
`test_set_from_env_partial_update`, and
`test_set_from_env_invalid_values`.
> 
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Author: ba11b0y