chore: chain138-open-snap canonical repo, submodule, publish script

- Point AGENTS.md at Defi-Oracle-Tooling/chain138-snap-minimal; document nested submodule in SUBMODULE_RELATIONSHIP_MAP
- Bump metamask-integration submodule (chain138-snap-minimal nested submodule on Gitea)
- Add publish-chain138-open-snap.sh with canonical repo comment

Made-with: Cursor

docs/11-references/SUBMODULE_RELATIONSHIP_MAP.md

@@ -34,6 +34,12 @@
 | **explorer-monorepo** | `explorer-monorepo/` | https://github.com/Order-of-Hospitallers/chain-138-explorer.git | Blockchain explorer | smom-dbis-138 |
 | **metamask-integration** | `metamask-integration/` | git@github.com:Defi-Oracle-Meta-Blockchain/metamask-integration.git | MetaMask integration | smom-dbis-138 |
 | **fireblocks-integration** | `fireblocks-integration/` | https://gitea.d-bis.org/d-bis/fireblocks-integration.git | Fireblocks Web3 (Chain 138 RPC, docs) | smom-dbis-138 (RPC) |
+
+#### Nested under metamask-integration
+
+| Path | Repository | Purpose |
+|------|------------|---------|
+| `metamask-integration/chain138-snap-minimal/` | https://github.com/Defi-Oracle-Tooling/chain138-snap-minimal.git | npm package **`chain138-open-snap`** (Chain 138 Open Snap). Registered as a nested submodule; use **`git submodule update --init --recursive`** from the repo root (or from `metamask-integration/` after `submodule update`) so this path is populated. Publish from proxmox: `scripts/deployment/publish-chain138-open-snap.sh`. |
 | **alltra-lifi-settlement** | `alltra-lifi-settlement/` | https://github.com/bis-innovations/LiFi_Pay_Alltra_Integration_Submodule.git | LiFi/Alltra settlement | None |
 | **cross-chain-pmm-lps** | `cross-chain-pmm-lps/` | https://gitea.d-bis.org/d-bis/cross-chain-pmm-lps.git | cW* M1 public-chain single-sided PMM stabilization mesh (bot, pool topology, peg bands, oracles) | smom-dbis-138 / token-mapping (reference) |
 | **ai-mcp-pmm-controller** | `ai-mcp-pmm-controller/` | https://gitea.d-bis.org/d-bis/ai-mcp-pmm-controller.git | 5701 MCP hub for DODO PMM (read-only + risk scoring, pool allowlist, policy gate) | See [AI_AGENTS_57XX_DEPLOYMENT_PLAN.md](../02-architecture/AI_AGENTS_57XX_DEPLOYMENT_PLAN.md) Appendix F |