Delete v0 code (python, rust) minus parts still used in allocators.

[johnwhumphreys]

Python APIs were already removed.

Sam will remove the rust code that is no longer used for v0; but some pieces of allocators are still used.

Migrate remaining allocator usage to simple bootstrap (or break into another issue if needed).

[johnwhumphreys]

Sam's working on it.

[johnwhumphreys]

Sam published a diff last week to get rid of the v1 code under Monarch/hyperactor (not mesh). Marius send a stack of diffs which may do the same. Will be done relatively soon.

[johnwhumphreys]

Sam says only things that are left is inside of hyperactor mesh. Marius's stack on top addresses the latter part and he is working on the shims.