refactor: shared session load path for session and export APIs (#125) #281

Job	Run time
mypy	20s
API integration tests + coverage (ubuntu-latest)	26s
ruff + pip-audit (macos-latest)	22s
Frontend unit tests (vitest) (windows-latest)	1m 1s
API integration tests + coverage (windows-latest)	1m 5s
Frontend unit tests (vitest) (macos-latest)	38s
ruff + pip-audit (windows-latest)	1m 1s
pytest (macos-latest)	35s
pytest (windows-latest)	1m 23s
Frontend unit tests (vitest) (ubuntu-latest)	25s
pytest (ubuntu-latest)	43s
Verify prod requirements.txt is sufficient	7s
Performance benchmarks (gated)	46s
ruff + pip-audit (ubuntu-latest)	20s
API integration tests + coverage (macos-latest)	18s
	9m 30s

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