induction does not populate instance-implicit arguments

Prerequisites

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[ ] Check that your issue is not already filed: https://github.com/leanprover/lean4/issues
[ ] Reduce the issue to a minimal, self-contained, reproducible test case. Avoid dependencies to Mathlib or Batteries.
[ ] Test your test case against the latest nightly release, for example on https://live.lean-lang.org/#project=lean-nightly (You can also use the settings there to switch to “Lean nightly”)

Description

The induction tactic does not handle instance-implicit arguments, as it treats them as regular implicits.

Context

Zulip thread

Steps to Reproduce

Run the following:
```
class Foo (α : Type)
```

instance : Foo Nat where

@[elab_as_elim] def Foo.induction_no (P : ∀ (α : Type) [Foo α], Prop) (nat : P Nat) (α : Type) [ohno : Foo α] : P α := sorry @[elab_as_elim] def Foo.induction_ok (P : ∀ (α : Type) [Foo α], Prop) (nat : P Nat) (α : Type) (ohok : Foo α) : P α := sorry

example (α : Type) [Foo α] : α = Nat := by induction α using Foo.induction_no with | nat => rfl

example (α : Type) [Foo α] : α = Nat := by induction α, ‹Foo α› using Foo.induction_ok with | nat => rfl



**Expected behavior:** Both inductions should succeed

**Actual behavior:** The first one fails with "failed to infer implicit target ohno". It should be synthesizing the target via typeclass search, since it is in square brackets.

### Versions

* 4.8.0-rc1
* 4.9.0-nightly-2024-05-21

### Additional Information

[Additional information, configuration or data that might be necessary to reproduce the issue]

### Impact

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leanprover / lean4