make A[begin:stride:end] work

[bjarthur]

also mostly from claude

[mkitti]

Thr main deficit is that begin and end do not work for indexing, I believe.

[bjarthur]

they work for me with this PR. i'll add some tests.

julia> size(A)
(1000, 20000)

julia> A[1:3:10,1]
TensorStore(UInt32, rank=1, shape=(4,))

julia> A[1:3:10,1].read().result()
4-element PyArray{UInt32, 1}:
 0x00000000
 0x00000000
 0x00000000
 0x00000000

julia> A[begin:3:10,1].read().result()
4-element PyArray{UInt32, 1}:
 0x00000000
 0x00000000
 0x00000000
 0x00000000

julia> A[end-10:3:end,1].read().result()
4-element PyArray{UInt32, 1}:
 0x00000000
 0x00000000
 0x00000000
 0x00000000

[Copilot]

Pull request overview

Adds missing Julia array-indexing hooks so begin:stride:end slicing works on TensorStoreWrapper views (including labeled sub-views), and validates the behavior with new tests.

Changes:

• Implemented Base.axes(w, d), Base.firstindex(w, d), and Base.lastindex(w, d) for TensorStoreWrapper and IndexDomainWrapper.
• Added tests covering firstindex/lastindex and strided slicing with begin:2:end on both full and labeled sub-views.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
test/runtests.jl	Adds assertions for firstindex/lastindex and begin:2:end slicing size behavior.
src/TensorStoreWrapper.jl	Adds dimension-specific axes/firstindex/lastindex to enable begin/end lowering in slicing.

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