### 1. Handling React className migration
The PR fixes an issue when migrating React components to tailwind v4
with the migration tool, that the first class after `className="` is
ignored.
For example, when migrating
```JSX
<div className="shadow"></div>
```
`shadow` will not be migrated to `shadow-sm` .
This is because in `is-safe-migration.ts`, it tests the line before
candidate with regex `/(?<!:?class)=['"]$/`. This basically skips the
migration for anything like `foo="shadow"`, with only exception for Vue
(eg. `class="shadow"`).
The PR changes the regex from
```regex
/(?<!:?class)=['"]$/
````
to
```regex
/(?<!:?class|className)=['"]$/
```
which essentially adds a new exception specifically for React's
`className="shadow"` case.
### 2. Removing redundant rules
Besides, I found that several other rules in
`CONDITIONAL_TEMPLATE_SYNTAX` being redundant since they are already
covered by the rule above, so I removed them. If we prefer the previous
explicit approach, I can revert it.
## Test plan
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Explain how you tested your changes. Include the exact commands that you
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Tests added for both the Vue and React classes to prevent false negative
cases.
---------
Co-authored-by: Jordan Pittman <jordan@cryptica.me>
47d6a023e3