fix(ci): bump mcp-publisher v1.4.1 → v1.7.9

The MCP Registry deploy of v1.7.5 (PR modelcontextprotocol/registry#1229)
moved OIDC audience binding from a hardcoded 'mcp-registry' constant
to per-deployment URLs derived from --registry. Our pinned v1.4.1
binary still requests the legacy audience and is rejected:

  invalid audience: expected https://registry.modelcontextprotocol.io,
  got [mcp-registry]

v1.4.6 npm publish succeeded but MCP Registry publish failed for this
reason. v1.7.9 derives the correct audience by default.

Author: jordanburke

.github/workflows/publish.yml

@@ -57,7 +57,7 @@ jobs:
 
       - name: Install MCP Publisher
         run: |
-          curl -L "https://github.com/modelcontextprotocol/registry/releases/download/v1.4.1/mcp-publisher_$(uname -s | tr '[:upper:]' '[:lower:]')_$(uname -m | sed 's/x86_64/amd64/;s/aarch64/arm64/').tar.gz" | tar xz mcp-publisher
+          curl -L "https://github.com/modelcontextprotocol/registry/releases/download/v1.7.9/mcp-publisher_$(uname -s | tr '[:upper:]' '[:lower:]')_$(uname -m | sed 's/x86_64/amd64/;s/aarch64/arm64/').tar.gz" | tar xz mcp-publisher
           chmod +x ./mcp-publisher
 
       - name: Login to MCP Registry