So it can't be an escalation because Israel has been bombing Iran directly (bases, consulate) for years?
You are correct that I am not following.
Oy, bases and consulates are not the same. Israel has never bombed Iran directly, bombing their foreign bases is not considered a direct attack, especially when the bases are there to orchestrate attacks against you. (i.e. IRGC bases in Syria to help Hezbollah with logistics, weapon transfers etc. to attack Israel)
Bombing an Embassy/Consulate is a step ahead. Israel has not been doing that before, but just did, according to Iran and others who view the annex building as an attack on the Consulate.
Bombing (raining!) missiles on another homeland is the absolute offence and the strongest form of openly declaring war.