feat: mvs algorithm for 'version' in kcl.mod is supported in the add command

[zong-zhe]

1. Does this PR affect any open issues?(Y/N) and add issue references (e.g. "fix #123", "re #123".):

• N
• Y

re #465

2. What is the scope of this PR (e.g. component or file name):

3. Provide a description of the PR(e.g. more details, effects, motivations or doc link):

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Other

4. Are there any breaking changes?(Y/N) and describe the breaking changes(e.g. more details, motivations or doc link):

• N
• Y

5. Are there test cases for these changes?(Y/N) select and add more details, references or doc links:

• Unit test
• Integration test
• Benchmark (add benchmark stats below)
• Manual test (add detailed scripts or steps below)
• Other

[coveralls]

Pull Request Test Coverage Report for Build 10735345446

Details

• 70 of 118 (59.32%) changed or added relevant lines in 6 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.2%) to 41.836%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/client/resolver.go	4	5	80.0%
pkg/client/visitor.go	5	7	71.43%
pkg/downloader/downloader.go	0	7	0.0%
pkg/client/update.go	56	75	74.67%
pkg/package/modfile.go	0	19	0.0%

Files with Coverage Reduction	New Missed Lines	%
pkg/downloader/downloader.go	1	40.93%

Totals
Change from base Build 10718340714:	0.2%
Covered Lines:	3436
Relevant Lines:	8213

---

💛 - Coveralls