Fix Foundry Skills local workflow

[Jiahui-Gu]

Summary

• update Foundry Skills provisioning to the current azure-ai-projects versioned upload API
• mark the uploaded version as default and pin the compatible SDK range
• allow the trusted read-only load_skill tool to complete non-interactive Responses requests
• update the sample documentation to match the working local workflow

Local verification

• provisioned both sample skills in a fresh environment
• started the exact repaired commit locally on the assigned repair port
• received HTTP 200 readiness and a completed representative Responses invocation
• observed two completed load_skill calls and both documented canary tokens