refactor: add baseDir to context

[czy88840616]

1、将 baseDir，appDir 注入到上下文中，方便获取
2、增加 mm.cluster 对 midway 框架的识别

[codecov-io]

Codecov Report

Merging #19 into master will increase coverage by 2.77%.
The diff coverage is 50%.

@@            Coverage Diff             @@
##           master      #19      +/-   ##
==========================================
+ Coverage   75.29%   78.07%   +2.77%     
==========================================
  Files          71       71              
  Lines        2097     2194      +97     
  Branches      314      338      +24     
==========================================
+ Hits         1579     1713     +134     
+ Misses        398      364      -34     
+ Partials      120      117       -3

Impacted Files	Coverage Δ
packages/midway-core/src/loader.ts	79.34% <100%> (+2.68%)	⬆️
packages/midway-web/src/decorators/application.ts	100% <100%> (ø)	⬆️
packages/midway-mock/src/index.ts	63.15% <20%> (-15.42%)	⬇️
packages/context/src/annotation/objectDef.ts	84.37% <0%> (-12.06%)	⬇️
packages/context/src/base/FunctionDefinition.ts	47.72% <0%> (-0.66%)	⬇️
packages/context/src/base/ObjectDefinition.ts	100% <0%> (ø)	⬆️
packages/context/src/base/ObjectCreator.ts	49.23% <0%> (+3.07%)	⬆️
packages/context/src/factory/common/Autowire.ts	56.25% <0%> (+4.16%)	⬆️
packages/context/src/factory/container.ts	90.9% <0%> (+8.61%)	⬆️
... and 4 more

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