affine-scalrep's findUnusedStore incorrectly classified an
affine.vector_store as dead when a subsequent store wrote to the same
base index but with a smaller vector type. A vector<1xi64> store at
[0,0] does not fully overwrite a vector<5xi64> store at [0,0], so the
first store must be preserved.
The loadCSE function in the same file already had the correct
type-equality check for loads; this patch adds the analogous check for
stores in findUnusedStore.
Fixes#113687
Assisted-by: Claude Code
f6ffdbcbae