text: Title: DOC: ceil, floor, etc. changes in 2.0 not represented in docs
  Body: ### Describe the issue:
  
  As [ceil's doc](https://numpy.org/doc/2.1/reference/generated/numpy.ceil.html) claims:
  > The return is the ceiling of each element in x, with float dtype. This is a scalar if x is a scalar.
  
  However, I found that NumPy-2 breaks this contract.
  
  ### Reproduce the code example:
  
  ```python
  import numpy as np
  a = np.array([1], dtype="int64")
  b = np.ceil(a)
  print(b.dtype)
  ```
  
  
  ### Error message:
  
  ```shell
  >>> import numpy as np
  >>> a = np.array([1], dtype="int64")
  >>> b = np.ceil(a)
  >>> print(b.dtype)
  int64
  
  
  I test it in NumPy 1.20.3:
  >>> import numpy as np
  >>> a = np.array([1], dtype="int64")
  >>> b = np.ceil(a)
  >>> print(b.dtype)
  float64
  ```
  
  
  ### Python and NumPy Versions:
  
  2.1.0
  3.10.12 (main, Jul 29 2024, 16:56:48) [GCC 11.4.0]
  
  ### Runtime Environment:
  
  [{'numpy_version': '2.1.0',
    'python': '3.10.12 (main, Jul 29 2024, 16:56:48) [GCC 11.4.0]',
    'uname': uname_result(system='Linux', node='42e7fc5f4d8e', release='6.8.0-49-generic', version='#49~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Wed Nov  6 17:42:15 UTC 2', machine='x86_64')},
   {'simd_extensions': {'baseline': ['SSE', 'SSE2', 'SSE3'],
                        'found': ['SSSE3',
                                  'SSE41',
                                  'POPCNT',
                                  'SSE42',
                                  'AVX',
                                  'F16C',
                                  'FMA3',
                                  'AVX2'],
                        'not_found': ['AVX512F',
                                      'AVX512CD',
                                      'AVX512_KNL',
                                      'AVX512_KNM',
                                      'AVX512_SKX',
                                      'AVX512_CLX',
                                      'AVX512_CNL',
                                      'AVX512_ICL']}},
   {'architecture': 'Haswell',
    'filepath': '/usr/local/lib/python3.10/dist-packages/numpy.libs/libscipy_openblas64_-ff651d7f.so',
    'internal_api': 'openblas',
    'num_threads': 24,
    'prefix': 'libscipy_openblas',
    'threading_layer': 'pthreads',
    'user_api': 'blas',
    'version': '0.3.27'}]
  
  ### Context for the issue:
  
  _No response_