feat: add Nodeclaim & Machine provision to RAG Engine controller

[bangqipropel]

Reason for Change:
add Nodeclaim and Machine provision to RAG Engine controller

Requirements

• added unit tests and e2e tests (if applicable).

Issue Fixed:

Notes for Reviewers:

[codecov]

Codecov Report

Attention: Patch coverage is 31.52866% with 215 lines in your changes missing coverage. Please review.

Project coverage is 52.85%. Comparing base (5c30038) to head (ee088ea).
Report is 37 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/controllers/ragengine_controller.go	29.78%	185 Missing and 13 partials ⚠️
pkg/controllers/workspace_controller.go	43.75%	9 Missing ⚠️
api/v1alpha1/zz_generated.deepcopy.go	0.00%	5 Missing ⚠️
pkg/controllers/ragengine_status.go	72.72%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #622      +/-   ##
==========================================
- Coverage   58.18%   52.85%   -5.34%     
==========================================
  Files          30       34       +4     
  Lines        2987     4221    +1234     
==========================================
+ Hits         1738     2231     +493     
- Misses       1149     1870     +721     
- Partials      100      120      +20     

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