[Merged by Bors] - fix(RepresentationTheory): move Equiv.coe_invFun to the correct symm notion to fit the statement as it suggests

[JX-Mo]

The current statement of lemma coe_invFun : φ.invFun = φ.symm := rfl actually reads φ.symm as⇑φ.toLinearEquiv.symm. However the context tends to make Representation.Equiv as the simp normal form, not φ.toLinearEquiv. We move it to where Representation.Equiv.symm has been defined so that the RHS has the correct form to get access to other API lemmas more directly.

[github-actions]

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[JX-Mo]

easy

[github-actions]

PR summary e42dff0012

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 (regex)

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

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

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

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

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

Declarations diff (Lean)

✅ Lean-aware diff — post-build, computed from the Lean environment (commit e42dff0).

• +0 new declarations
• −0 removed declarations

No declaration differences.

---

No changes to strong technical debt.

No changes to weak technical debt.

Current commit e42dff0012
Reference commit b4a18d6453

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/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).

[github-actions]

✅ PR Title Formatted Correctly

The title of this PR has been updated to match our commit style conventions.
Thank you!

[Whysoserioushah]

LGTM!

[jjdishere]

Thanks,

maintainer merge

[github-actions]

🚀 Pull request has been placed on the maintainer queue by jjdishere.

[kbuzzard]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• ci (staging) / Post-Build Step
• ci (staging) / Post-CI job
• ci (staging) / Build
• ci (staging) / Test and lint
• ci (staging) / Lint style