feat: Add sessions

[coveralls]

Pull Request Test Coverage Report for Build 6958289616

• 3 of 385 (0.78%) changed or added relevant lines in 9 files are covered.
• 3 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-7.4%) to 40.279%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/domain/models/backend.rs	0	1	0.0%
src/domain/models/session.rs	0	2	0.0%
src/config.rs	0	3	0.0%
src/application/ui.rs	0	5	0.0%
src/main.rs	0	32	0.0%
src/domain/services/app_state.rs	0	70	0.0%
src/domain/services/sessions.rs	0	96	0.0%
src/application/cli.rs	0	173	0.0%
<!--	Total:	3	385	0.78%	-->

Files with Coverage Reduction	New Missed Lines	%
src/domain/services/app_state.rs	1	37.4%
src/application/cli.rs	2	0.0%
<!--	Total:	3		-->

Totals
Change from base Build 6958257179:	-7.4%
Covered Lines:	837
Relevant Lines:	2078

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💛 - Coveralls