auto-task(positionOperatorSchwartz): fix doc-string mislabeling it the parity operator

[jstoobysmith]

Summary

Fixed one factually incorrect doc-string in
Physlib/QuantumMechanics/OneDimension/Operators/Position.lean.

Location: Physlib/QuantumMechanics/OneDimension/Operators/Position.lean:62

Before → After:

• Before: /-- The parity operator on the Schwartz maps is defined as the linear map from 𝓢(ℝ, ℂ)to itself, such thatψis taken tofun x => x * ψ x. -/
• After: /-- The position operator on the Schwartz maps is defined as the linear map from 𝓢(ℝ, ℂ)to itself, such thatψis taken tofun x => x * ψ x. -/

Evidence the original was wrong

The doc-string documents positionOperatorSchwartz
(Position.lean:64),
which is Distribution.powOneMul ℂ — the map ψ ↦ fun x => x * ψ x (confirmed by the
positionOperatorSchwartz_apply simp lemma). Multiplication by the coordinate x is the
position operator, and the enclosing section header (Position.lean:54) reads
"## The position operator on Schwartz maps".

The genuine parity operator is a different declaration, parityOperatorSchwartz
(Parity.lean:52-53),
which maps ψ ↦ fun x => ψ (-x) — not x * ψ x. The old wording was a copy-paste of that
doc-string, mislabeling the position operator as the "parity operator".

How to confirm in one step

Compare the doc-string at Position.lean:62 against the declaration name
positionOperatorSchwartz and its body Distribution.powOneMul ℂ (→ x * ψ x) two lines below:
the map is multiplication by x (position), not ψ(-x) (parity), so "position operator" is the
correct label.

Only the one word parity → position was changed; no code was touched. lake build of the
module succeeds, and ./scripts/lint-style.sh and lake exe runPhyslibLinters both pass.

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