feat(ir): implement HoistConstant rule for lifting py.Constant in ilist.ForEach|ilist.Map

[zhenrongliew]

Adds HoistConstant, a rewrite that lifts py.Constant statements out of the closure bodies passed to ilist.ForEach / ilist.Map, and re-introduces them as closure captures.

# before # after%x = py.constant.constant10%x = py.constant.constant10%body = func.lambdabody(%x) { %hoisted = py.constant.constant2^1(%body_self, %i): %body = func.lambdabody(%x, %hoisted) {
│ %x_1 = func.getfield(%body_self, 0) ^1(%body_self, %i):
│ %4 = py.constant.constant2 │ %4 = func.getfield(%body_self, 1)
│ %5 = py.binop.mult(%x_1, %4) │ %x_1 = func.getfield(%body_self, 0)
│ %6 = py.binop.add(%5, %i) │ %5 = py.binop.mult(%x_1, %4)
} │ %6 = py.binop.add(%5, %i)
py.ilist.map(fn=%body, collection=%2) }
 py.ilist.map(fn=%body, collection=%2)

Tested behavior:

• ilist.ForEach/ilist.Map` , constants leave the body, captures grow.
• Loop-variant ops stay put, only constants.
• py.Constant appear before lambda.
• Nested fixpoint, hoist through nested closures.
• Newly folded constants also hoist.
• Idempotent.

closes#698

[github-actions]

☂️ Code Coverage

current status: ✅

Overall Coverage

Statements	Covered	Coverage	Threshold	Status
11740	10581	90%	0%	🟢

New Files

File	Coverage	Status
src/kirin/dialects/ilist/rewrite/hoist_constant.py	91%	🟢
TOTAL	91%	🟢

Modified Files

File	Coverage	Status
src/kirin/dialects/ilist/rewrite/_init_.py	100%	🟢
TOTAL	100%	🟢

updated for commit: 33a3166 by action🐍

[github-actions]

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[codecov]

Codecov Report

❌ Patch coverage is 91.66667% with 4 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/kirin/dialects/ilist/rewrite/hoist_constant.py	91.48%	4 Missing ⚠️

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