Add watcher to sync data in etcd to local cache

[hanahmily]

• Add a unit test to verify that the fix works.
• Tests(including UT, IT, E2E) are added to verify the new feature.
• If this pull request closes/resolves/fixes an existing issue, replace the issue number. Fixes [Bug] [Metadata] Use etcd watch API to update schema cache skywalking#10892.
• Update the CHANGES log.

[codecov-commenter]

Codecov Report

Merging #319 (9a9e42c) into main (c37bc25) will increase coverage by 1.14%.
The diff coverage is 63.38%.

@@            Coverage Diff             @@
##             main     #319      +/-   ##
==========================================
+ Coverage   39.74%   40.89%   +1.14%     
==========================================
  Files         105      107       +2     
  Lines       11337    11376      +39     
==========================================
+ Hits         4506     4652     +146     
+ Misses       6373     6256     -117     
- Partials      458      468      +10     

Files Changed	Coverage Δ
banyand/measure/metadata.go	72.83% <ø> (+23.64%)	⬆️
banyand/metadata/schema/node.go	7.69% <0.00%> (+0.54%)	⬆️
banyand/metadata/schema/property.go	0.00% <0.00%> (ø)
banyand/metadata/schema/shard.go	0.00% <0.00%> (ø)
banyand/metadata/schema/topn.go	0.00% <0.00%> (ø)
banyand/stream/metadata.go	78.80% <ø> (+25.56%)	⬆️
pkg/run/closer.go	0.00% <0.00%> (ø)
banyand/metadata/schema/etcd.go	47.01% <44.82%> (-10.14%)	⬇️
banyand/metadata/schema/kind.go	58.76% <58.76%> (ø)
banyand/metadata/client.go	39.31% <66.66%> (+0.84%)	⬆️
... and 9 more

... and 3 files with indirect coverage changes

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