fix(deps): bump @salesforce/agents from 1.10.2 to 1.10.3 @W-23371674

[Christian-Vallejos]

What

Bump @salesforce/agents from 1.10.2 to 1.10.3 (package.json + yarn.lock).

Why

1.10.3 contains the fetchMcpServer empty-body fix
(forcedotcom/agents#318),
which resolves a 300s HeadersTimeoutError hang on sf agent mcp fetch.

A bodyless POST over HTTP/2 left the request stream half-open, so
jsforce/undici never received the response headers and the call blocked
until the 300s headers timeout. 1.10.3 sends an explicit empty {} body.

agents@1.10.3 is published on npm, but the CLI pins the exact version from
this plugin's lockfile, so the fix does not reach sf until this bump is
released.

Test plan

• yarn build + full test suite green (ran on push via pre-push hook).
• Verified locally that a CLI built with agents@1.10.3 drops sf agent mcp fetch from 300s to ~5s across every MCP server tested.