Android Qwen thinking mode prompt support

[kirklandsign]

Use different prompts according to mode

cc @mergennachin @iseeyuan @lucylq @helunwencser @tarun292 @kimishpatel @jackzhxng

[pytorch-bot]

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❌ 2 New Failures

As of commit 4e8d276 with merge base 8ee4487 ():

NEW FAILURES - The following jobs have failed:

• pull / unittest / macos / macos-job (gh)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 1
• pull / unittest-editable / macos / macos-job (gh)
  backends/xnnpack/test/ops/test_multiply.py::TestMul::test_qs8_mul2

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