Update core to bundle all errors using error module,

[panarch]

• Bundle and export all errors using error module.
• Rename result module to "error" for out-of-core-workspace users.
• Update storages/ and test-suite/ codes to use global error module.

[coveralls]

Pull Request Test Coverage Report for Build 4900718228

• 10 of 10 (100.0%) changed or added relevant lines in 6 files are covered.
• 13 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.005%) to 98.955%

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Files with Coverage Reduction	New Missed Lines	%
core/src/executor/fetch.rs	13	96.95%

Totals
Change from base Build 4900246167:	-0.005%
Covered Lines:	43643
Relevant Lines:	44104

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💛 - Coveralls