Refactor and maintain A22 database tables / indexes

[clezag]

Database has steadily grown, to the point where we now have a 300+ GB traffic table, with multiple indexes of 100+ GB.

CPU load is high, correlating with busy day time and falling during nighttime.

There is already a similar issue open for mobility data: noi-techpark/bdp-core#270

We should try a few things to reign in the exploding database:

• determine if we can delete old records or shift them to an archive table
• partitioning
• rebuild and adjust the already optimized partial index for timestamps > dec 2021
• Remove the btree stationcode index that overlaps with the partial one
• try brin indexes for timestamps
• optimize column data types as most of them are needlessly large

[clezag]

During the last modifications to the a22 traffic connector, the full stationcode index was removed, and the partial index updated to oct 2024, freeing up a few 100GB of space, and lowering CPU load