feat(privacy): screening policy decides an open-note deposit's subject

[avi-starkware]

An Invoke returning open-note deposits now consults its target's OpenNoteScreeningPolicy, inside
the existing non-empty-deposits guard so an Invoke funding nothing is still never screened.
Required — every unlisted address — makes the target itself the tx's screening subject; Exempt
raises no requirement; Delegated reverts with the new DELEGATED_SCREENING_UNSUPPORTED until the
pool can ask a target which addresses to screen. The devnet e2e now lists the swap and lending
executors Exempt, the posture the deployed pools carry, since Required would refuse their notes.

Co-Authored-By: Claude Opus 5 noreply@anthropic.com

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This change is 

[avi-starkware]

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• feat(anonymizer): a shadow account is its interaction's associated address #950
• feat(privacy): a delegated depositor names its deposits' associated addresses #949
• test(privacy): fold the block-timestamp cheat into the apply helpers #948
• test(privacy): shared fixtures for deposit and open-note tests #947
• feat(privacy): screening policy decides an open-note deposit's subject #946 👈 (View in Graphite)
• feat(privacy): single screening-subject requirement collection #945
• feat(privacy): one screening-policy list for open-note depositors #944
• main

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[remollemo]

@remollemo reviewed 10 files and all commit messages, and made 2 comments.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on avi-starkware and Yoni-Starkware).

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packages/privacy/src/privacy.cairo line 1013 at r1 (raw file):

            // Apply deposits to open notes returned by Invoke. `contract_address` is the depositor,
            // and its policy decides what the deposits require. An Invoke returning no deposits
            // never consults the policy list.

Suggestion:

            // Apply deposits to open notes returned by Invoke. `contract_address` is the depositor.
            // Screening - if reqruired, and its subject is defined by the depositor screening policy. and applicaband its policy decides what the deposits require. An Invoke returning no deposits

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packages/privacy/src/privacy.cairo line 1017 at r1 (raw file):

                match self.open_note_depositor_screening_policies.read(contract_address) {
                    // The depositor funds open notes only under a screening attestation for its
                    // own address.

remove