Add emergency-pause gating to commitment_marketplace settlement entrypoints

[1nonlypiece]

📌 Description

commitment_core integrates shared_utils::Pausable and EmergencyControl, and
commitment_nft/attestation_engine/allocation_logic expose pause/unpause.
commitment_marketplace, however, has no Pausable integration, so buy_nft,
accept_offer, place_bid, and end_auction cannot be halted during an incident
even though they move user funds.

This issue adds emergency pause gating to the marketplace settlement paths.

🎯 Requirements and Context

• Integrate shared_utils::Pausable (PAUSED_KEY) and admin-gated pause/unpause.
• Gate all fund-moving entrypoints (list_nft settlement, buy_nft, accept_offer, place_bid, end_auction) with require_not_paused.
• Read-only getters must remain callable while paused.
• No regressions to fee logic or the payment-token allowlist.

🛠️ Suggested Execution

1. Fork the repo and create a branch

git checkout -b security/marketplace-pausable

2. Implement changes

• Add Pausable wiring and pause/unpause to contracts/commitment_marketplace/src/lib.rs with /// docs.
• Update docs/EMERGENCY.md equivalent in contracts/EMERGENCY.md and docs/SECURITY_CONSIDERATIONS.md.

3. Test and commit

• Extend contracts/commitment_marketplace/src/tests.rs.
• Run: cargo test --target wasm32v1-none --release
• Edge cases: paused buy rejected, paused bid rejected, getter while paused ok, non-admin pause rejected.

Example commit message

fix: add emergency pause gating to marketplace settlement

✅ Guidelines

• Minimum 95% test coverage on the gated paths.
• Document the incident-response procedure.
• Timeframe: 96 hours.

🏷️ Labels

type-security · area-contracts · MAYBE REWARDED · GRANTFOX OSS · OFFICIAL CAMPAIGN

💬 Community & Support

• Join the CommitLabs contributor Discord to coordinate and get unblocked fast: https://discord.gg/WV7tdYkJk
• Introduce yourself before starting to avoid duplicate work.
• Maintainers triage actively and review fast.

[dangelo352]

I can take this one. I will add marketplace pause/unpause wiring, gate the fund-moving settlement paths, keep read-only getters available while paused, and include focused tests for paused rejection plus non-admin pause rejection.