hexagon: support I32 CPY and CONT

[kurquhar]

Overview

Add I32 CPY and CONT support to the hexagon backend

Additional information

Motivation is bringing the main graph ops of the LFM2.5-DSpark draft model onto hexagon, instead of using the CPU fallback.

Mostly this was an exercise of extending the current FP32 and FP16 support to also include INT32->INT32.

Validation commands:

python scripts/snapdragon/run.py --install-dir pkg-wos-i32-cont --devices HTP0 -- test-backend-ops -o CONT -b HTP0
python scripts/snapdragon/run.py --install-dir pkg-wos-i32-cont --devices HTP0 -- test-backend-ops -o CPY -b HTP0

Before: 12 CONT and 11 CPY test cases not supported
After: same 23 test cases [OK]

The corresponding test cases for FP32 and FP16 continue to pass, as before.

Requirements

• I have read and agree with the contributing guidelines Yes
• AI usage disclosure: Yes, for reasoning, code changes, and testing. All code was reviewed by me (human).

Assisted-by: OpenCode

[max-krasnyansky]

@lhez please review/ack. I'll wait for CI to clear and merge.