Rename the Claude plugin to simular-box and add its README and privacy policy URL #21

Requested by: chenchen (@chenchenSimular), 2026-11-05.

Rationale

We are submitting box to the Claude plugin directory (guide: https://claude.ai/artifact/Pdrs2AFaWXtLQzRyw5sGiq, blockers B5 and B7). Box, Inc. already has a verified "Box" plugin and connector in Claude's directory, so our plugin id box will likely be refused as taken or held as a known brand. Decision: list as "box by Simular" and use the plugin id simular-box. The directory also blocks a plugin folder without a README and asks for a privacy policy URL.

What

• Rename the Claude plugin id from box to simular-box (claude/.claude-plugin/plugin.json and the simular-box marketplace entry). The install command becomes simular-box@simular-box.
• Update every place that names the old id: READMEs, the CLI's Claude Code client (cli/src/clients/claude-code.js), its tests and the e2e install matrix, and box-portal's install docs if they name it.
• Migrate existing installs: npx @simular-ai/box connect (and doctor) replaces an installed box@simular-box with simular-box@simular-box without losing the user's settings; remove handles both ids.
• Add claude/README.md (at least 40 words: what box is, what the plugin adds, how to sign in, links) and "privacyPolicyUrl": "https://www.simular.ai/product-sai/privacy" in plugin.json.
• Not in scope: the plugin icon (claude/.claude-plugin/icon.png), which waits on the logo from Ang; it can be set only once, on first submit.

Done when

• claude plugin validate ./claude passes with no warnings other than the missing icon.
• A fresh install with simular-box@simular-box and an upgrade from box@simular-box both work in the CLI's install matrix.
• Docs show the new command; a CLI release carries the migration.