fix(Tensors): rank the tensor action above the Tensorial action

[zhikaip]

Changes

Tensors/Basic.lean: instSMul, actionT and the DistribMulAction on S.Tensor c get priority := high + 1.

SMulCommClass k G (S.Tensor c) and SMulCommClass G k (S.Tensor c) added (the second via SMulCommClass.symm, as in Mathlib); the G k order also added for Tensorial types.

as a result, multiple set_option backward.isDefEq.respectTransparency false removed and a maxHeartbeats 600000.

Why: an instance diamond on g • t

Two SMul G (S.Tensor c) instances exist:

1. Tensor.instSMul in Tensors/Basic.lean, the direct action. All *_equivariant lemmas are
   stated with it.
2. Tensorial.smulAction in Tensorial.lean, defined for any [Tensorial S c M] as
   g • m = toTensor.symm (g • toTensor m). Since S.Tensor c is Tensorial via self
   (toTensor = LinearEquiv.refl), it also applies to bare tensors, and with priority := high
   it won.

So in a goal, g • t carried instance 2; the lemma's left-hand side carries instance 1. They are
defeq (unfold refl) but not syntactically equal, hence rw/simp failed while exact and
the respectTransparency false option (unfolding fallback, paid for in heartbeats) worked.

Fix: rank instance 1 at high + 1. Bare tensors now use the direct action. Instance 2 keeps
high and still governs Tensorial types and M ⊗ M₂, where it must beat Mathlib's left-only
TensorProduct action (Tensorial.smul_prod); lowering it instead breaks that lemma.
The SMulCommClass instances are stated for instance 1 so smul_comm fires on it.

fix found by claude and confirmed/edited by myself

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[jstoobysmith]

Looks good to me. Approved.