- Introduced `mosaic_tpu` backend in `paged_attention.zig` and updated related structures to accommodate TPU-specific parameters and options.
- Implemented `raggedPagedAttention` function in `flashattn.zig` to handle TPU-specific attention logic.
- Enhanced `Buffer` struct in `buffer.zig` with a new method `toPrefix1dSlice` for copying prefixes of rank-1 buffers across shards.
- Updated `Platform` struct in `platform.zig` to manage TPU IR runtime initialization and deinitialization.
- Modified `env` function in `testing.zig` to return a platform instance or an error, improving error handling in tests.
- Adjusted various test cases to handle platform initialization errors gracefully.
- Cleaned up unused imports and ensured consistent error handling across the codebase.