Add uniffi holder API #6258

Job	Run time
aries_vcx_clippy (credx,vdrtools_wallet)	3m 46s
workflow-setup	25s
aries_vcx_clippy (vdr_proxy_ledger)	5m 31s
verify-code-formatting	24s
aries_vcx_no_features_clippy	2m 29s
workspace_clippy	3m 49s
aries_vcx_core_clippy (credx,vdrtools_wallet)	3m 7s
aries_vcx_core_clippy (vdr_proxy_ledger)	3m 25s
workflow-setup-check	2s
build-docker-vdrproxy	12s
test-integration-aries-vcx	14m 4s
code-coverage-aries-vcx-integration-modular-libs	15m 33s
test-unit-workspace	6m 7s
x86_64-unknown-linux-gnu	14m 43s
test-integration-aries-vcx-mysql	3m 41s
x86_64-unknown-linux-musl	8m 41s
x86_64-apple-darwin	11m 4s
aarch64-apple-darwin	32m 7s
test-integration-did-crate	3m 3s
test-integration-libvcx	2m 45s
test-integration-node-wrapper (18.x)	8m 12s
test-integration-aries-vcx-vdrproxy	16m 16s
publish-docker-vdrproxy	3s
make-release	0s
publish-napi	0s
publish-node-wrapper	0s
publish-agent-core	0s
	2h 39m 29s

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