sec(deps): bump x/crypto for GO-2026-6303 blocking shipped-image scan

[cristim]

Summary

The shipped cudly image now fails the mandatory advisory scan because the root binary includes golang.org/x/crypto v0.53.0, which is affected by fixable advisory GO-2026-6303. The advisory is fixed in v0.55.0.

Current behavior

Every PR that runs CI - Build & Test fails in Build Docker Image at scripts/scan-shipped-image.sh, even when the PR does not touch Go dependencies. This currently blocks the open PR queue from satisfying the required green-CI merge gate.

Steps to reproduce

1. Check out current origin/main at ae331a0c4cbe6956b0b4a2ee33c45a5118076be8.
2. Build the production image using the CI workflow.
3. Run bash scripts/scan-shipped-image.sh <image-tag>.
4. Observe FIXABLE GO-2026-6303 in golang.org/x/crypto fixed in v0.55.0 for /app/cudly and exit 1.

The failure is visible in Actions run 33205697618 from PR #1884.

Expected behavior

The shipped binary contains no dependency with a published fix for a detected advisory, and the Docker image scan exits 0.

Proposed fix

• Update golang.org/x/crypto from v0.53.0 to at least v0.55.0 in the root module and keep the provider module dependency graph consistent where required.
• Run module tidy without unrelated dependency churn.
• Rebuild the production image and run scripts/scan-shipped-image.sh against it.
• Run the root and affected provider module test suites plus the repository's pinned lint/security checks.

References

• Blocked PR: feat(mcp): annotate every tool with MCP ToolAnnotations #1884
• Failed workflow run: https://github.com/LeanerCloud/CUDly/actions/runs/33205697618
• Current declarations: go.mod:67, providers/gcp/go.mod:60, providers/azure/go.mod:35

Severity

High. This is a fixable advisory in the shipped production binary and currently blocks every new PR from reaching a green merge gate.