chore: release 1.2.0

[tianzhou]

Bumps the version to 1.2.0 (pnpm version, synced into plugin/.claude-plugin/plugin.json, plugin/.mcp.json, and server.json).

Changes since 1.1.0

Features

• Bearer token auth for the HTTP transport via --auth-token / DBHUB_AUTH_TOKEN, with comma-separated tokens for zero-downtime rotation (feat(server): add bearer token auth for HTTP transport #390)
• Breaking: execute_sql returns per-statement result sets for multi-statement queries, wired up to frontend tabs (feat(connectors)!: return per-statement result sets, wire up frontend tabs #389)

Fixes

• SQL Server: enforce max_rows across UNION/INTERSECT/EXCEPT compound queries (Fix: SQL Server max_rows not enforced across UNION/INTERSECT/EXCEPT #388)
• MySQL: kill the server-side query on timeout instead of leaking it back into the connection pool (fix(mysql): kill server-side query on timeout instead of leaking it into the pool #386)

Docs & chores

• Render env var names in command-line flag docs (docs: render env var names in command-line flag docs #391)
• Trim verbose tool descriptions and fix search_objects parameter drift
• Revise health_check tool description
• README fixes
• Single-source version sync for the plugin and server.json

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR prepares the dbhub project for the 1.2.0 release by bumping the package version and syncing that version into the shipped plugin and MCP registry metadata files.

Changes:

• Bump npm package version from 1.1.0 → 1.2.0 in package.json.
• Sync the release version to the Claude plugin manifest and MCP launcher config.
• Sync the release version to server.json (MCP registry metadata).

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
package.json	Bumps the published package version to 1.2.0.
plugin/.claude-plugin/plugin.json	Updates plugin manifest version to 1.2.0.
plugin/.mcp.json	Updates the npx @bytebase/dbhub@... pinned version to 1.2.0.
server.json	Updates MCP registry metadata and package version to 1.2.0.