refactor: Add a configuration manager as a crate

[TaKO8Ki]

Issue number and link

Fixes: #220

This pull request also bumps up minimal supported Rust version to 1.65 because of https://github.com/time-rs/time/releases/tag/v0.3.21.

Describe your changes

Checklist before requesting a review

• I follow the Semantic Pull Requests rules (bugfix/feature)
• I specified links to related issues (must: bugfix, want: feature)
• I have performed a self-review of my code (bugfix/feature)
• I have added thorough tests (bugfix/feature)
• I have edited ## [Unreleased] section in CHANGELOG.md following keep a changelog syntax (bugfix/feature)
• I {made/will make} a related pull request for documentation repo (feature)

[codecov]

Codecov Report

Patch coverage: 87.27% and project coverage change: -0.07 ⚠️

Comparison is base (378893c) 84.77% compared to head (830b7a5) 84.70%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #262      +/-   ##
==========================================
- Coverage   84.77%   84.70%   -0.07%     
==========================================
  Files         215      215              
  Lines       12692    12687       -5     
==========================================
- Hits        10760    10747      -13     
- Misses       1932     1940       +8     

Impacted Files	Coverage Δ
...rc/stream_engine/autonomous_executor/task_graph.rs	94.70% <ø> (-0.10%)	⬇️
...engine/autonomous_executor/test_support/factory.rs	75.00% <0.00%> (ø)
springql-config/src/lib.rs	85.71% <85.71%> (ø)
springql-core/src/pipeline/test_support/fixture.rs	82.12% <100.00%> (-0.20%)	⬇️
...onomous_executor/task/sink_task/sink_writer/net.rs	86.45% <100.00%> (ø)
...cutor/task/source_task/source_reader/net_client.rs	89.28% <100.00%> (-0.13%)	⬇️
...cutor/task/source_task/source_reader/net_server.rs	95.79% <100.00%> (-0.04%)	⬇️
springql/tests/e2e_high_level_rs.rs	100.00% <100.00%> (ø)

... and 4 files with indirect coverage changes

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[laysakura]

Thanks 🎉