Azure tempdb filling up while trying to convert a large table to columnstore... how to mitigate?
Bulk inserting into a CLUSTERED COLUMNSTORE index by itself shouldn't be blowing up tempdb.  Rows are read and put into compressed rowgroups in chunks of 1 million, there is no reason for long term tempdb usage.
I believe the problem is the non-clustered index ix_SRR_JobId on temp.SRR (JobId);
First try moving the index creation to after the bulk insert:
insert Logs(Message) values('Populating SRR table...');
insert into temp.SRR with (tablock) select * from dbo.SRR (nolock);
create index ix_SRR_JobId on temp.SRR (JobId) WITH (SORT_IN_TEMPDB = OFF);

This will substantially reduce tempdb pressure.
If tempdb is still blowing up, then try loading the data in smaller chunks. How you partition the data doesn't really matter, but, it should be based on the leading column(s) of an existing clustered index (unique or not).  The chunks should be small enough to load but large enough to avoid excessive &quot;delta rowgroups&quot;  (Columnstore Indexes: Data Loading Guidance).
As a starting point, aim for 10-20 chunks of equal size.  If the base table is 2 TB, then these would be 100-200 GB.  Adjust up or down until you get it to work.
For example, if column1 is a datetime, then try loading by year or quarter or month.