Refactor manifest schema to use external library

[gowthamrao]

Decoupled schema from runtime by using coreason-manifest.
Refactored manifest.py to re-export library classes.
Updated topology.py to adapt new schema structure.
Updated runner.py, handlers.py, and strategies/council.py to support new node types and config structures.
Updated all unit and integration tests to use valid manifests.
Bumped version to 0.4.1.

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PR created automatically by Jules for task 2348186524950383015 started by @gowthamrao

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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