Identify Fusable Chains

Given a list of ops with kinds in {'gemm', 'elementwise', 'reduction', 'memory'}, group consecutive indices that can fuse into a single kernel.

Signature: def identify_fusable_chain(ops: list) -> list

• ops: list of {'kind': str} dicts
• Fusion rules:
  • elementwise → elementwise: fuse
  • gemm → elementwise: fuse (epilogue fusion)
  • any reduction or memory op breaks the chain — it stands alone
  • any other transition breaks the chain

Return a list of lists of indices, in order.

Example: [gemm, elementwise, elementwise, reduction, elementwise] → [[0, 1, 2], [3], [4]].