Add support for Japanese subject

[FlechaMaker]

• Add Japanese subject format
• Fix citation alert normalization to support the subject with number of citation
• Add test case for Japanese alert (My Google account receives ".com.au" links in Japanese alert, so I also added ".com.au" to the test case.)

[bzz]

Thank you so much for sharing the improvements! 🙇 Apologies for totally missing it due to vacations and work that, recently, involved less research & paper reading.

Overall it looks great, but if you don't mind - I'm going to add the CI first so we could use this to test it.