AIRSpecializeChannelWrapAndStride, AIRRtToNPU: Refactor wrap-and-stride canonicalizer

[erwei-xilinx]

• Unify the multiple hasNElements into two variants: hasNImpureOps and hasNElements.
• Refactor AIRSpecializeChannelWrapAndStride and AIRRtToNPU to use the same wrap-and-stride canonicalizer and for-loop folding methods.
• Refactor some methods in AIRRtToNPU to use pattern matching.
• Refactor evaluateConstantsInMap to support both symbol and dim inputs.