[TUBEMQ-501] Adjust max message size check logic

[gosonzhang]

1. Adjust the processing logic of Producer, Broker, and Master, and increase the maximum message length to dynamically check and process;
2. Adjust the unit of the maximum message packet length setting value from byte to MB
3. Optimize some implementation logic

[codecov-io]

Codecov Report

Merging #391 (220a331) into master (fb70aa8) will increase coverage by 0.02%.
The diff coverage is 0.30%.

@@             Coverage Diff             @@
##             master    #391      +/-   ##
===========================================
+ Coverage      7.44%   7.46%   +0.02%     
- Complexity      469     473       +4     
===========================================
  Files           267     268       +1     
  Lines         29306   29438     +132     
  Branches       4834    4857      +23     
===========================================
+ Hits           2181    2197      +16     
- Misses        26647   26766     +119     
+ Partials        478     475       -3     

Impacted Files	Coverage Δ	Complexity Δ
.../apache/tubemq/client/producer/AllowedSetting.java	28.57% <0.00%> (+28.57%)	1.00 <0.00> (+1.00)
.../tubemq/client/producer/SimpleMessageProducer.java	13.06% <0.00%> (ø)	2.00 <0.00> (ø)
...ava/org/apache/tubemq/corebase/TBaseConstants.java	0.00% <ø> (ø)	0.00 <0.00> (ø)
...a/org/apache/tubemq/corebase/utils/MixedUtils.java	0.00% <0.00%> (ø)	0.00 <0.00> (ø)
...pache/tubemq/corebase/utils/SettingValidUtils.java	0.00% <0.00%> (ø)	0.00 <0.00> (ø)
...n/java/org/apache/tubemq/corerpc/RpcConstants.java	0.00% <ø> (ø)	0.00 <0.00> (ø)
...ache/tubemq/server/broker/BrokerServiceServer.java	0.00% <0.00%> (ø)	0.00 <0.00> (ø)
...va/org/apache/tubemq/server/broker/TubeBroker.java	0.00% <0.00%> (ø)	0.00 <0.00> (ø)
...mq/server/broker/metadata/ClusterConfigHolder.java	0.00% <0.00%> (ø)	0.00 <0.00> (?)
...he/tubemq/server/broker/msgstore/MessageStore.java	0.00% <0.00%> (ø)	0.00 <0.00> (ø)
... and 16 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update fb70aa8...220a331. Read the comment docs.