issue: #38399
- Make a timetick-commit-based write ahead buffer at write side.
- Add a switchable scanner at read side to transfer the state between
catchup and tailing read
Signed-off-by: chyezh <chyezh@outlook.com>
issue: #33285
- use reader but not consumer for pulsar
- advanced test framework
- move some streaming related package into pkg
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Signed-off-by: chyezh <chyezh@outlook.com>