[CT-14] Implement emergency pause mechanism for escrow contract

[mftee]

Problem

If a critical vulnerability is discovered in the escrow contract after deployment, there is no way to stop new funds from being deposited while a patch is prepared. All in-flight escrow funding operations remain exposed to the vulnerability with no emergency stop.

Proposed Solution

Implement an admin-controlled pause mechanism in a new escrow contract inside contracts/package/escrow-pausable/ that halts new deposits while preserving the ability to release or refund existing funds.

Note: All work must be done inside the contracts/package/ directory. Do not modify any existing contract files outside this folder.

Acceptance Criteria

• pause() and unpause() functions are admin-only
• When paused: fund_escrow() returns ContractPaused error
• When paused: open_dispute() returns ContractPaused error
• When paused: release_funds() and refund() continue to work (existing funds can always exit)
• is_paused() is a publicly callable read-only function
• A ContractPaused event is emitted with the admin address and timestamp when paused
• Unit tests cover: fund fails when paused, release succeeds when paused, non-admin pause attempt (Unauthorized)

[limxiy]

@limxiy has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I’d like to work on this issue. I have experience implementing secure pause and access-control mechanisms in Soroban smart contracts, and I can build the pausable escrow contract with proper admin restrictions and emergency handling.

Planned implementation:

• Create the new escrow-pausable contract inside contracts/package/
• Add admin-only pause() and unpause() functions
• Block fund_escrow() and open_dispute() while paused
• Ensure release_funds() and refund() continue functioning during paused states so funds are never trapped
• Implement publicly callable is_paused() view function
• Emit ContractPaused event with admin address and timestamp
• Add comprehensive unit tests for pause enforcement, authorized access, and allowed fund exits during pause mode

All work will remain scoped to:

• contracts/package/escrow-pausable/

ℹ️ Repo Maintainers: To accept this application, review their application or assign @limxiy to this issue.

[drips-wave]

Congratulations, @limxiy! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @limxiy: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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