Extend operator-typo SyntaxError suggestions (`=<`, `=>`, `=!`) to `if/while` other conditions

Follow-up #151375

In that PR we added helpful SyntaxError messages for common operator typos: =< suggests <=, => suggests >=, and =! suggests !=.

These suggestions currently only work when the typo appears in a plain statement. like

'a => b' invalid syntax. Maybe you meant '>=' instead of '=>'?

So this is for extending in if, while, or other conditions:

These only fire for bare statements, so if a => b: still gives the generic error, no? That is probably fine for a first iteration (the = < tokenization makes it look like an assignment), but maybe we should add a test documenting it or a follow-up issue for the if/while case.

Originally posted by @pablogsal in https://github.com/python/cpython/pull/151375#discussion_r3683730462

I'm planning to work on this and submit a PR shortly after the follow up merged, please avoid PR in this

まず PR #151375 と既存の SyntaxError 提案実装を読んで、単独の文で演算子のタイプミスがどのように検出されるかを理解します。その動作を if、while、その他の条件ケースに拡張し、続いてそれらの形式を対象とするテストを追加または更新して、提案されるメッセージを検証します。