Make docs hooks, clai and pydantic-evals Windows compatible (use utf-8)

[Danipulok]

Hey!

Summary
I'm using Windows. While I was working on #3523, I had issues with rendering docs because of docs/.hooks

I decided to change some places inside docs and clai and pydantic-evals, so that they use utf-8.

Windows by default uses other encoding, and utf-8 needs to be specified.
(At least I really don't like this behavior at all, and it will be changed in python 3.15)

Note
There're some more places where utf-8 can be specified.
I noticed in some tests you actually specify utf-8, so probably you want to minimize usage of utf-8
Then I can leave utf-8 only in .docs, if it's acceptable

[Viicos]

Might be worth enabling the https://docs.astral.sh/ruff/rules/unspecified-encoding/ rule?

[Danipulok]

@Viicos hey!
Happy to enable it and lint the whole project if that works for you.
Shall I do it?

[Danipulok]

I updated the PR, please check
@Viicos, @DouweM

Changes:

• Add encoding='utf-8' everywhere;
• Add PLW1514 rule for ruff;
• Enable preview mode for [tool.ruff];
• Refactored docs/.hooks/test_snippets.py‎ to make them Windows-compatible;

Notes:

1. If [tool.ruff.format] preview = false is unset, about 75 files are changed via formatter;

2. docs/.hooks/test_snippets.py‎ tests failed on Windows with:

            finally:
>               os.unlink(f.name)
E               PermissionError: [WinError 32] The process cannot access the file because it is being used by another process: 'C:\\Users\\Dan\\AppData\\Local\\Temp\\tmpfbq5k65p.py'

docs\.hooks\test_snippets.py:104: PermissionError
                                                   Summary of Failures                                                    
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━┓
┃  File                          ┃  Function                        ┃  Function Line  ┃  Error Line  ┃  Error            ┃
┡━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━┩
│  docs\.hooks\test_snippets.py  │  test_parse_file_sections_basic  │  81             │  104         │  PermissionError  │
└────────────────────────────────┴──────────────────────────────────┴─────────────────┴──────────────┴───────────────────┘
Results (0.67s):
         1 failed
        24 passed

Now they are working

3. I also removed f.flush() link everywhere in docs/.hooks/test_snippets.py‎, because it had no effect when using Path.write_text(...)

4. I also removed those 3 lines in docs/.hooks/test_snippets.py‎,, which did nothing

5. PLW1514 does not work perfectly, so I had to manually search for open, write_text and read_text

[Danipulok]

It also seems that pinned ruff version is old and does not catch most of the encoding errors (regarding my note 5)
Should I update it in this / other PR or no?

Edit:
But it catches only 4 more errors on the latest ruff version, so I'm not sure about it...
(Catches about 4 errors out of ~60)

astral team seems to be checking initial var's type, and if it's like this: bundle_path: Path | None = None, that it won't be considered as Path, even after asserts
Also it seems they can't resolve some transformations like Path(...) / "foo.py"

Here are the docs: https://docs.astral.sh/ruff/rules/unspecified-encoding/
Here is the source code: https://github.com/astral-sh/ruff/blob/main/crates%2Fruff_linter%2Fsrc%2Frules%2Fpylint%2Frules%2Funspecified_encoding.rs#L57

IMHO, they could just check for method names, but maybe they don't want to do it
I don't think much can be done here, except for creating issues in their repo