## Summary
- Replace the hardcoded thread pool max threads limit (16) with a
configurable parameter `common.threadCoreCoefficient.maxThreadsSize`,
default 16, only effective when greater than 0
- Add missing Resize watchers for middle and low priority thread pools
- When `maxThreadsSize` changes dynamically, update the limit first then
resize all pools to ensure correct ordering
issue: #48378
Signed-off-by: sijie-ni-0214 <sijie.ni@zilliz.com>