Hotfix: contract execution error

[kobayurii]

This pull request updates the project for compatibility with the latest nearcore version and introduces several hotfixes to improve contract execution and configuration parsing. The changes also include a version bump and a minor database query adjustment.

Version and Compatibility Updates

• Updated NEARCORE_VERSION to 2.7.0 and NEARD_COMMIT to 9ae6990f170591242ae79fce812d245024762f77 in .cargo/config.toml for nearcore compatibility.
• Bumped workspace package version to 0.4.1 in Cargo.toml.
• Updated CHANGELOG.md to document the new release, hotfixes, and supported versions.

Database Query and Hotfixes

• Modified SQL query in rpc_server.rs to select only data_value instead of both data_key and data_value, simplifying the data retrieval.
• Changed the return logic in rpc_server.rs to construct a QueryData object directly from the query result, supporting the hotfix for contract execution.