feat(Combinatorics/GraphLike): introduce SymmGraphLike typeclass

[Jun2M]

Per discussion at (#graph theory > HasAdj), This PR extends GraphLike typeclass defined in #36743 for graphs with symmetric darts (SimpleGraph and Graph, not Digraph).

Main definitions

• SymmGraphLike V D E Gr: A typeclass extending GraphLike with together with inv, an involution function on darts that swaps src and tgt.
• NoMultiEdgeSymmGraphLike V D E Gr: A typeclass extending NoMultiEdgeGraphLike and SymmGraphLike.

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• depends on: feat(Combinatorics/GraphLike): introduce GraphLike typeclass #36743
• depends on: feat(Combinatorics/GraphLike): GraphLike with no multi edges #39047

[github-actions]

PR summary 311bc48b92

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.Combinatorics.GraphLike.Basic (new file)	489

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Declarations diff

+ Adj.left_mem
+ Adj.right_mem
+ Adj.symm
+ DartAdj
+ GraphLike
+ NoMultiEdgeGraphLike
+ SymmGraphLike
+ adj_comm
+ adj_source_target
+ adj_target_source
+ dartSym2
+ dartSym2_comp_inv
+ dartSym2_eq_iff
+ dartSym2_eq_mk'_iff
+ dartSym2_eq_mk'_iff'
+ dartSym2_inv
+ dartSym2_mk
+ dartSymm
+ dartSymm_dartSymm
+ dartSymm_involutive
+ dartSymm_mk
+ dart_eq_of_source_target_eq
+ darts_ext
+ instance : Std.Symm (Adj G)
+ instance [DecidableRel (Adj G)] : DecidablePred (· ∈ D(G))
+ inv_mem_darts
+ mem_darts_iff_adj
+ noMultiEdgeSymmGraphLike
+ source_target_inj
+ toProd

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.

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No changes to strong technical debt.

No changes to weak technical debt.