chore(AlgebraicGeometry/EllipticCurve/*): remove redundant names

[Multramate]

Clean up a few redundant/bad names:

• nonsingular_zero_of_Δ_ne_zero is a special case of nonsingular_of_Δ_ne_zero, which itself is a (very easy) special case of equation_iff_nonsingular_of_Δ_ne_zero, and similarly with nonsingular and equation_iff_nonsingular
• equation_neg(_of) and nonsingular_neg(_of) are special cases of equation_neg_iff and nonsingular_neg_iff
• mapFun and toClassFun are function versions of the group homomorphisms map and toClass
• mk_XYIdeal'_mul_mk_XYIdeal'_of_Yeq should have been named mk_XYIdeal'_neg_mul according to naming conventions
• all instance names since they can be named automatically

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[github-actions]

PR summary a4f6c76f37

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

+ equation_iff_nonsingular
+ equation_iff_nonsingular_of_Δ_ne_zero
+ instance : AddZeroClass W.Point
+ mk_XYIdeal'_neg_mul
++ instance : Neg W.Point
++ instance [Nontrivial R] : Zero W'.Point
+++ instance : Add W.Point
- instAddZeroClassPoint
- of
-- instNegPoint
-- instZeroPoint
--- instAddPoint

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 script/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).