chore: bump lotus submodule pointer

[bigduu]

Summary

• advance the Lotus submodule pointer to the merged Provider Settings legacy-UI retirement
• carry Lotus #177 and Lotus PR #229 into the Zenith integration pin
• leave every other submodule pointer and root file unchanged

Submodule Updates

Submodule	Previous	New	Rationale
lotus	f5d5f1b80acbd2ad65e9b59220fac8f5c783d43d	7218e7bcff3143247b8dbf50545abe4f43eb7738	Use canonical Provider Instance settings exclusively, surface canonical load failures, preserve credential/default/Copilot behavior, and prevent instance deletion from leaving dangling model refs or reactivating legacy-only authority.

Test Plan

• verified the new gitlink exactly matches bigduu/Lotus main@7218e7bcff3143247b8dbf50545abe4f43eb7738
• verified the old pin is an ancestor of the new pin
• verified the root diff contains only the lotus mode-160000 entry
• git diff --check
• nested Lotus checkout is clean
• upstream Lotus exact-head gates on PR #229: Frontend Checks and E2E Tests passed
• upstream local verification: 276 Vitest files, 3421 passed / 1 skipped; type-check, lint, Prettier, production build, and 2 focused real-backend E2E tests passed

Screenshots

The UI screenshots and real-Bamboo browser dogfood evidence are documented in Lotus PR #229. This integration PR changes only the root gitlink.

[bigduu]

Agent review: APPROVED for exact head cf15d20eb6a94338351751b609acb43ced7bd440 against base 7d63bfc23715852461da50968bb52097ec5ef094.

Independent read-only verification confirmed:

• the commit has the expected base as its only parent;
• the recursive raw diff contains only the lotus mode-160000 entry, from f5d5f1b80acbd2ad65e9b59220fac8f5c783d43d to 7218e7bcff3143247b8dbf50545abe4f43eb7738;
• the old Lotus pin is the merge base and the new pin is exactly one commit ahead, with no divergence;
• the new pin is Lotus PR #229's merge commit, is the current Lotus main, and corresponds to closed/Done Lotus #177;
• the PR body contains the required ## Submodule Updates exact old/new SHAs and rationale;
• git diff --check and both Submodule Guard checks pass;
• no review thread or code/security blocker remains.