Refactor deserialization process

[fktn-k]

This PR has improved the internal implementation for the deserialization feature with the following changes:

• The stacks of indentations and nodes were managed separately but are now handled as a single stack variable with context state types.
• The values for tracking the current input position are now of the uint32_t type, not of the unnecessarily large size_t type which was used before with no convincing reason.
• The traversal codes which find a parse context with a matching indentation have been improved by removing unnecessary traversals.
• Unnecessary variables/type-aliasings are removed which became unused during previous refactorings of the lexer and the input/unicode handlings.

In addition, unnecesary node object instanciations are removed in the test cases for the deserializer.

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• Changes are described in the pull request or in a referenced issue.
• The test suite compiles and runs without any error.
• The code coverage on your branch is 100%.
• The documentation is updated if you added/changed a feature.

Please don't

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[github-actions]

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[coveralls]

Pull Request Test Coverage Report for Build 8899336069

Details

• 155 of 155 (100.0%) changed or added relevant lines in 7 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 100.0%

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Totals
Change from base Build 8882147308:	0.0%
Covered Lines:	3535
Relevant Lines:	3535

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