Add assist plugin v0.1.25

[victorborshak]

Summary

Adds the assist plugin v0.1.25 to the CLI plugin index.

• Plugin: assist (AI agent design, coding, and deployment assistant)
• Version: 0.1.25
• Release: https://github.com/datarobot/dr-agent-cli/releases/tag/v0.1.25
• SHA256: 285c9f211fa7a49d0b65daebbfb6a788578c056528d8063cbfbad62479d3d3f1

Test Plan

• dr plugin install assist installs successfully
• dr assist --help shows usage
• dr assist launches the agent UI

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Note

Low Risk
Metadata-only index update with pinned SHA256; no application or security logic changes.

Overview
Registers assist v0.1.25 as the newest entry in docs/plugins/index.json, prepended to the existing assist version list with tarball URL, SHA256, and release date 2026-06-04.

No other plugins or index structure are modified; clients that read the first listed version will treat 0.1.25 as the latest installable release.

^{Reviewed by Cursor Bugbot for commit 578c3bc. Configure here.}