`-DMLIR_ENABLE_EXPENSIVE_PATTERN_API_CHECKS=ON` might have found some invalid API usages

While the [documentation](https://mlir.llvm.org/getting_started/Debugging/#detecting-invalid-api-usage) states that there might be false positives, I think it might be worth a look into the individual test cases and patterns.
If there are no false positives, adding `-DMLIR_ENABLE_EXPENSIVE_PATTERN_API_CHECKS=ON` to the CI could be beneficial.
```
Failed Tests (32):
CIRCT :: Conversion/LoopScheduleToCalyx/convert_pipeline.mlir
CIRCT :: Conversion/SCFToCalyx/cider_source_location.mlir
CIRCT :: Conversion/SCFToCalyx/convert_controlflow.mlir
CIRCT :: Conversion/SCFToCalyx/convert_func.mlir
CIRCT :: Conversion/SCFToCalyx/convert_memory.mlir
CIRCT :: Conversion/SCFToCalyx/convert_simple.mlir
CIRCT :: Conversion/SCFToCalyx/errors.mlir
CIRCT :: Dialect/Arc/arc-canonicalizer.mlir
CIRCT :: Dialect/Arc/canonicalizers.mlir
CIRCT :: Dialect/Calyx/canonicalization.mlir
CIRCT :: Dialect/Comb/canonicalization.mlir
CIRCT :: Dialect/FIRRTL/SFCTests/GrandCentralInterfaces/Wire.fir
CIRCT :: Dialect/FIRRTL/SFCTests/data-taps.fir
CIRCT :: Dialect/FIRRTL/SFCTests/invalid-interpretations.fir
CIRCT :: Dialect/FIRRTL/SFCTests/invalid-reg-pass.fir
CIRCT :: Dialect/FIRRTL/SFCTests/mem-taps.fir
CIRCT :: Dialect/FIRRTL/canonicalization.mlir
CIRCT :: Dialect/FIRRTL/ref.mlir
CIRCT :: Dialect/FIRRTL/simplify-mems.mlir
CIRCT :: Dialect/HW/canonicalization.mlir
CIRCT :: Dialect/HW/inline.mlir
CIRCT :: Dialect/Handshake/canonicalization.mlir
CIRCT :: Dialect/LLHD/Canonicalization/extract.mlir
CIRCT :: firtool/async-reset.fir
CIRCT :: firtool/chirrtl.fir
CIRCT :: firtool/firtool.fir
CIRCT :: firtool/import-ref.fir
CIRCT :: firtool/lower-memories.fir
CIRCT :: firtool/prefixMemory.fir
CIRCT :: firtool/spec/refs/define.fir
CIRCT :: firtool/spec/refs/nested_refproducer.fir
CIRCT :: firtool/sv-attr.fir

Testing Time: 2.55s

Total Discovered Tests: 812
Unsupported : 12 (1.48%)
Passed : 762 (93.84%)
Expectedly Failed: 6 (0.74%)
Failed : 32 (3.94%)
```

The observed errors are:
- `LLVM ERROR: operation finger print changed`
- `LLVM ERROR: pattern returned success but IR did not change`
- `LLVM ERROR: IR failed to verify after pattern application`

Start by rerunning the listed CIRCT tests with -DMLIR_ENABLE_EXPENSIVE_PATTERN_API_CHECKS=ON and compare the three reported LLVM errors across the Conversion, Dialect, and firtool test paths. Done means determining whether each failure is a false positive or an invalid pattern API usage, addressing the confirmed cases, and establishing whether the flag should be added to CI.

Written by the indexing model from the issue text.