`simp?` after a focus dot produces incorrectly indented lines

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
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Description

When simp? appears directly after a focus dot, clicking on the "Try this:" suggestion inserts code where the second and following lines are at the same indentation as the first, instead of indented by two additional spaces.

MWE:

@[simp]
theorem a_lemma_with_a_very_loooooooooooooooooooooooooooooooooooooooooooong_name (n : Nat) :
    2 * n = n + n := by
  exact Nat.two_mul n

@[simp]
theorem another_lemma_with_a_very_loooooooooooooooooooooooooooooooooooooooooooong_name (n : Nat) :
    1 + n = n + 1 :=
  Nat.add_comm ..

example (n : Nat) : 1 = 1 ∧ 1 + 2 * n = n + n + 1 := by
  constructor
  · rfl
  -- · simp? -- and then clicking on "Try this:" gives
  · simp only [a_lemma_with_a_very_loooooooooooooooooooooooooooooooooooooooooooong_name,
    another_lemma_with_a_very_loooooooooooooooooooooooooooooooooooooooooooong_name]

Context

See the discussion on Zulip.

Steps to Reproduce

See the MWE above.

Expected behavior:
The second and following lines of the inserted code should be indented by two additional spaces.

Actual behavior:
All lines have the same indentation.

Versions

Lean 4.14.0-rc2
Target: x86_64-unknown-linux-gnu

Impact

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Start by reproducing the MWE with Lean 4.14.0-rc2, placing simp? after the focus dot and clicking the “Try this:” suggestion. Trace the focus-dot suggestion insertion path and verify that the second and following inserted lines are indented two spaces further than the first, as shown in the expected behavior.