feat(Tactic/Positivity): make positivity work for types that are not partial orders

[HugLycan]

Make positivity work for types that are not partial orders

Most PositivityExt haven't been updated for non partial order cases yet. They will be updated in the later PR.

Strictness now depends on Option Q(PartialOrder $α) instead of Q(PartialOrder $α), and the constructors of Strictness now have their order typeclass arguments. In order to help Qq synth instances property, we have to move assertInstancesCommute to inner branch, manually add haveI' or explicitly pass the order typeclass instance into .positive/.nonnegative.

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✅ PR Title Formatted Correctly

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PR summary d048652946

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

+ compareHypNonzero
+ pow_zero_ne_zero

You can run this locally as follows

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

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

The doc-module for scripts/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/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).