Add safe config updating

[Efnilite]

Description

Changes

• Fixes New 'backups to keep' entry not generated for existing configs #7184
• Reformats all classes to be more up to date with code standards
  • Any non-new method changes are for improving code readability, improving the position of the methods in the class or using pattern matching.
• Deprecates the current method for config updating, replacing it with Config#updateNodes

About updateNodes
Config#updateNodes differs from the current behaviour of Config#setValues as it does not touch any nodes in the existing config ("the old config") that are also present in the config provided with Skript ("the new config"). This ensures safety for critical sections like the databases section.

First, the difference between the nodes of the new and old config is found. These nodes that are missing from the old config will then be added to the old config at the index (the amount of nodes prior to the current one) at which they were found in the new config.

Testing
From my testing, this only seems to break when the old config is made invalid by de-indenting one of the entry nodes. This means the path of the following nodes are all different until the start of the next section (at the same indentation as the currently de-indented entry node, not any children). As a node's path is used to determine whether it is missing from the config, this will cause these following nodes to de-indent as well, deleting the current section head. This seems to be fixed by adding a check for whether the parsed config is valid, by using SectionNode#isValid.

Limitations
Currently, outdated comments are not deleted and I'm not sure whether we want to support keeping user-added comments present. Should this be added?

Removed
My sanity

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Target Minecraft Versions: any
Requirements: none
Related Issues: #7184

[Moderocky]

I don't want the node classes to be reformatted in this PR.

[sovdeeth]

looks good overall but just want some testing assurances

[APickledWalrus]

As sovde's comment mentioned, I would like to see some config-updating tests for this. Otherwise, it looks great!

[APickledWalrus]

Just about ready

[APickledWalrus]

awesome!!