refactor: split ai editor feature capabilities

[Ricbet]

Types

• 🪚 Refactors

Background or solution

主要重构了 ai-editor.contribution 代码，之前是所有 ai editor 相关的 feature 能力都全写在了这里，不易维护。
现在重构成由每个单独的 feature 能力（如 code action、rename、inline-completion）等各自维护自己的 feature

Changelog

[railway-app]

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 392 lines in your changes are missing coverage. Please review.

Project coverage is 55.41%. Comparing base (5f617c1) to head (36fab2c).

Files	Patch %	Lines
.../browser/widget/inline-chat/inline-chat.handler.ts	0.00%	185 Missing and 28 partials ⚠️
...browser/contrib/code-action/code-action.handler.ts	0.00%	59 Missing and 14 partials ⚠️
...b/inline-completions/inline-completions.handler.ts	0.00%	53 Missing and 7 partials ⚠️
...ative/src/browser/contrib/rename/rename.handler.ts	0.00%	33 Missing and 1 partial ⚠️
packages/ai-native/src/browser/index.ts	0.00%	6 Missing ⚠️
...ser/contrib/inline-completions/completeProvider.ts	0.00%	1 Missing ⚠️
...contrib/inline-completions/prompt/importedFiles.ts	0.00%	1 Missing ⚠️
...rowser/contrib/inline-completions/prompt/prompt.ts	0.00%	1 Missing ⚠️
...ntrib/inline-completions/prompt/similarSnippets.ts	0.00%	1 Missing ⚠️
...rc/browser/contrib/terminal/ai-terminal.service.ts	0.00%	1 Missing ⚠️
... and 1 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3716      +/-   ##
==========================================
- Coverage   55.62%   55.41%   -0.21%     
==========================================
  Files        1527     1530       +3     
  Lines       92953    93306     +353     
  Branches    19099    19162      +63     
==========================================
+ Hits        51707    51710       +3     
- Misses      34190    34497     +307     
- Partials     7056     7099      +43     

Flag	Coverage Δ
jsdom	50.86% <0.00%> (-0.19%)	⬇️
node	15.55% <0.00%> (-0.06%)	⬇️

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