feat: add coe instances for spectrums

[xgenereux]

This PR adds Coe instances for the type PrimeSpectrum and similar.

For P: PrimeSpectrum, this means that when lean expects Ideal A, we can directly write P : Ideal A instead of P.asIdeal. The .asIdeal gets inserted automatically.

At the moment, I haven't set up the @[coe] to make delab into ↑P - it simply shows P.asIdeal in the infoview. If we want the ↑P I can add it.

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[github-actions]

PR summary c00fe67bb4

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

+ instance (R : Type*) [CommSemiring R] : Coe (MaximalSpectrum R) (Ideal R)
+ instance : Coe (HeightOneSpectrum R) (Ideal R)
+ instance : Coe (PrimeSpectrum R) (Ideal R)

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).

[faenuccio]

Can you add a bit of description to the PR?