fix: prevent lib/core/agent/index.js unexpectly loaded by plugin lo…

[njugray]

rename:

• lib/core/agent.js -> lib/core/worker/agent.js
• lib/worker/index.js -> lib/core/worker/application.js

Side effects from #egg-core/pull/156

[codecov-io]

Codecov Report

Merging #35 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master      #35   +/-   ##
=======================================
  Coverage   92.49%   92.49%           
=======================================
  Files          70       70           
  Lines        1053     1053           
=======================================
  Hits          974      974           
  Misses         79       79

Impacted Files	Coverage Δ
...ackages/beidou-core/lib/core/worker/application.js	100% <ø> (ø)
packages/beidou-core/lib/core/worker/agent.js	72.72% <ø> (ø)
packages/beidou-core/lib/beidou.js	100% <100%> (ø)	⬆️

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