chore(Tactic): rewrite order tactic docstring

[Vierkantor]

This PR rewrites the docstrings for the order tactic, to consistently match the official style guide, to make sure they are complete while not getting too long.

The order_core docstring also gets a little rewrite to make clearer that it is an implementation detail (and also explain exactly what it does).

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[github-actions]

PR summary 062adc5c07

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

No declarations were harmed in the making of this PR! 🐙

You can run this locally as follows

## summary with just the declaration names:
./scripts/pr_summary/declarations_diff.sh <optional_commit>

## more verbose report:
./scripts/pr_summary/declarations_diff.sh long <optional_commit>

The doc-module for scripts/pr_summary/declarations_diff.sh contains some details about this script.

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No changes to technical debt.

You can run this locally as

./scripts/reporting/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

[JovanGerb]

Thanks!

If order_core is an implementation detail, could you mark it as a local syntax? That way, it is not usable outside of this file, and it won't show up in the automatically generated documentation.

[joneugster]

Indeed, order_core not showing up in the generated docs seems preferrable.

LGTM otherwise, thanks!