feat: Implements get_connection_string

[cveticm]

1. Exposes the get_connection_string tool from the rust library.
2. Adds unit and e2e testing.
3. Defines exact versions for napi and napi-derive

JIRA ticket: MCP-154

[coveralls]

Pull Request Test Coverage Report for Build 17951418547

Details

• 40 of 145 (27.59%) changed or added relevant lines in 3 files are covered.
• 74 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-14.5%) to 42.47%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/lib.rs	0	11	0.0%
index.js	19	113	16.81%

Files with Coverage Reduction	New Missed Lines	%
index.js	74	13.7%

Totals
Change from base Build 17763240647:	-14.5%
Covered Lines:	399
Relevant Lines:	771

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💛 - Coveralls