Better detection of IntelliJ language injection comments

[InSyncWithFoo]

Summary

Enhances #14069.

Test Plan

A few tests are added to cover edge cases.

[InSyncWithFoo]

By the way, do we want that giant regex to be case-insensitive? type: ignore, pyright and SPDX-License-Identifier are a few non-examples.

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

✅ ecosystem check detected no linter changes.

[MichaReiser]

Could you help me review this more efficiently by listing yoour changes so that I don't have to diff the Regex?

For case-sensitivity: I think we should use case-sensitive for the suppression comments that are case-sensitive and allow case-insensitivity for the ones that are not.

I also think we should gate this change behind preview mode unless all changes relax the rule's strictness.

[InSyncWithFoo]

Here's a comparison table:

	Before (all case insensitive)	After
pylint		No change
pyright		Case sensitive
noqa		No change
nosec		No change
region/endregion		Case sensitive
type: ignore		Case sensitive
fmt	fmt:\s*(on|off)	fmt:\s*(on|off|skip), case sensitive
isort		No change
mypy		Case sensitive
SPDX-License-Identifier:		Case sensitive
encoding		No change

As for language=:

• Before: (?i) language=[a-zA-Z](?: ?[-_.a-zA-Z0-9]+)+(?:\s+prefix=\S+)?(?:\s+suffix=\S+)?
• After: language=[-_.a-zA-Z0-9]+