This PR adds the implementation of NEP-35's like= argument, allowing dispatch of array creation functions with __array_function__ based on a reference array.

* ENH: Add like= kwarg via __array_function__ dispatcher to asarray

* ENH: Add new function for __array_function__ dispatching from C

This new function allows dispatching from C directly, while also
implementing the new `like=` argument, requiring only minimal
changes to existing array creation functions that need to add
support for that argument.

* ENH: Add like= support to numpy.array

The implementation uses array_implement_c_array_function, thus
introducing minimal complexity to the original _array_fromobject
code.

* BUG: Fix like= dispatcher for np.full

* ENH: Remove np.asarray like= dispatcher via Python

np.asarray can rely on np.array's C dispatcher instead.

* TST: Add some tests for like= argument

Tests comprise some of the functions that have been implemented already:
* np.array (C dispatcher)
* np.asarray (indirect C dispatcher via np.array)
* np.full (Python dispatcher)
* np.ones (Python dispatcher)

* ENH: Remove like= argument during array_implement_array_function

* ENH: Add like= kwarg to ones and full

* BUG: prevent duplicate removal of `like=` argument

* ENH: Make `like=` a keyword-only argument

* ENH: Use PyUnicode_InternFromString in arrayfunction_override

Replace PyUnicode_FromString by PyUnicode_InternFromString to cache
"like" string.

* ENH: Check for arrayfunction_override import errors

Check and handle errors on importing NumPy's Python functions

* BUG: Fix array_implement_c_array_function error handling

* ENH: Handle exceptions with C implementation of `like=`

* ENH: Add `like=` dispatch for all asarray functions

Using Python dispatcher for all of them. Using the C dispatcher
directly on the `np.array` call can result in incorrect behavior.
Incorrect behavior may happen if the downstream library's
implementation is different or if not all keyword arguments are
supported.

* ENH: Simplify handling of exceptions with `like=`

* TST: Add test for exception handling with `like=`

* ENH: Add support for `like=` to `np.empty` and `np.zeros`

* TST: Add `like=` tests for `np.empty` and `np.zeros`

* ENH: Add `like=` to remaining multiarraymodule.c functions

Functions are:
* np.arange
* np.frombuffer
* np.fromfile
* np.fromiter
* np.fromstring

* TST: Add tests for multiarraymodule.c functions with like=

Functions are:
* np.arange
* np.frombuffer
* np.fromfile
* np.fromiter
* np.fromstring

* ENH: Add `like=` support to more creation functions

Support for the following functions is added:
* np.eye
* np.fromfunction
* np.genfromtxt
* np.identity
* np.loadtxt
* np.tri

* TST: Add `like=` tests for multiple functions

Tests for the following functions are added:
* np.eye
* np.fromfunction
* np.genfromtxt
* np.identity
* np.loadtxt
* np.tri

* TST: Reduce code duplication in `like=` tests

* DOC: Document `like=` in functions that support it

Add documentations for the following functions:
* np.array
* np.arange
* np.asarray
* np.asanyarray
* np.ascontiguousarray
* np.asfortranarray
* np.require
* np.empty
* np.full
* np.ones
* np.zeros
* np.identity
* np.eye
* np.tri
* np.frombuffer
* np.fromfile
* np.fromiter
* np.fromstring
* np.loadtxt
* np.genfromtxt

* ENH: Add `like=` to numpy/__init__.pyi stubs

* BUG: Remove duplicate `like=` dispatching in as*array

Functions `np.asanyarray`, `np.contiguousarray` and `np.fortranarray`
were dispatching both via their definitions and `np.array` calls,
the latter should be avoided.

* BUG: Fix missing check in array_implement_array_function

* BUG: Add missing keyword-only markers in stubs

* BUG: Fix duplicate keyword-only marker in array stub

* BUG: Fix syntax error in numpy/__init__.pyi

* BUG: Fix more syntax errors in numpy/__init__.pyi

* ENH: Intern arrayfunction_override strings in multiarraymodule

* STY: Add missing brackets to arrayfunction_override.c

* MAINT: Remove arrayfunction_override dict check for kwarg

* TST: Assert that 'like' is not in TestArrayLike kwargs

* MAINT: Rename array_implement_c_array_function(_creation)

This is done to be more explicit as to its usage being intended for
array creation functions only.

* MAINT: Use NotImplemented to indicate fallback to default

* TST: Test that results with `like=np.array` are correct

* TST: Avoid duplicating MyArray code in TestArrayLike

* TST: Don't delete temp file, it may cause issues with Windows

* TST: Don't rely on eval in TestArrayLike

* TST: Use lambda with StringIO in TestArrayLike

* ENH: Avoid unnecessary Py_XDECREF in arrayfunction_override

* TST: Make TestArrayLike more readable

* ENH: Cleaner error handling in arrayfunction_override

* ENH: Simplify array_implement_c_array_function_creation

* STY: Add missing spaces to multiarraymodule.c

* STY: C99 declaration style in arrayfunction_override.c

* ENH: Simplify arrayfunction_override.c further

Remove cleanup label from array_implementation_c_array_function,
simplifying the code. Fix unitialized variable warning in
array_implementation_array_function_internal.

* DOC: Use string replacement for `like=` documentation

Avoid repeating the full text for the `like=` argument by storing it as
a variable and using `replace` on each docstring.

* DOC: Update `like=` docstring

* TST: Test like= with array not implementing __array_function__

* TST: Add missing asanyarray to TestArrayLike

* ENH: Use helper function for like= dispatching

Avoid dispatching like= from Python implementation functions to improve
their performance. This is achieved by only calling a dispatcher
function when like is passed by the users.

* ENH: Rename array_function_dispatch kwarg to public_api

* BUG: Add accidentally removed decorator for np.eye back

* DOC: Add set_array_function_like_doc function

The function keeps Python files cleaner and resolve errors when __doc__
is not defined due to PYTHONOPTIMIZE or -OO .

* DOC: Add mention to like= kwarg being experimental

* TST: Test like= with not implemented downstream function

* DOC: Fix like= docstring reference to NEP 35.

* ENH: Prevent silent errors if public_api is not callable

* ENH: Make set_array_function_like_doc a decorator

* ENH: Simplify `_*_with_like` functions

* BUG: Fix multiple `like=` dispatching in `require`

* MAINT: Remove now unused public_api from array_function_dispatch

Co-authored-by: Sebastian Berg <sebastian@sipsolutions.net>

One of the header line was not long enough, make it the same length as
the title.

The section "Arguments" is usually called "Parameters". Update for
consistency.

Avoid the repeated call of `dedent` when a single call is enough. This micro-optimizes
the import time from around 100ms (or slightly above) by 4-6 ms. (PR: gh-14095)

xref GH-13624, GH-12028

TODO: update tests/CI for NUMPY_EXPERIMENTAL_ARRAY_FUNCTION=0

xref GH-12028

Current behavior:

>>> np.dot(None, None)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/shoyer/dev/numpy/numpy/core/overrides.py", line 175, in public_api
    implementation, public_api, relevant_args, args, kwargs)
TypeError: unsupported operand type(s) for *: 'NoneType' and 'NoneType'

>>> np.stack([], invalid=True)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/shoyer/dev/numpy/numpy/core/overrides.py", line 148, in public_api
    relevant_args = dispatcher(*args, **kwargs)
TypeError: _stack_dispatcher() got an unexpected keyword argument 'invalid'

With this change:

>>> np.dot(None, None)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<string>", line 6, in dot
TypeError: unsupported operand type(s) for *: 'NoneType' and 'NoneType'

>>> np.stack([], invalid=True)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<string>", line 4, in stack
TypeError: _stack_dispatcher() got an unexpected keyword argument 'invalid'