feat: tool prefix name

[hungran]

Closes: #333

introduce arg flag tool-prefix

so client able to add prefix name of tools, avoid conflict tool name with another mcp server

[Copilot]

Pull Request Overview

Adds support for an optional tool-prefix flag to disambiguate tool names by prepending a user-specified string.

• Introduce a tool-prefix CLI flag and bind it via Viper.
• Extend MCPServerConfig and StdioServerConfig to include ToolPrefix and propagate it into server registration.
• Update Toolset.RegisterTools and ToolsetGroup.RegisterAll to accept a prefix and register tools with prefixed names.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
pkg/toolsets/toolsets.go	Added createToolWithPrefixedName and updated RegisterTools to apply the prefix when registering tools.
internal/ghmcp/server.go	Added ToolPrefix to MCPServerConfig/StdioServerConfig and passed it into RegisterAll and dynamic toolset registration.
cmd/github-mcp-server/main.go	Defined the tool-prefix flag in Cobra, bound it to Viper, and populated the CLI config.

Comments suppressed due to low confidence (2)

pkg/toolsets/toolsets.go:106

• No unit tests were added to verify the new prefix logic in RegisterTools. Adding tests to confirm that tools are registered with the correct prefixed names would help prevent regressions.

func (t *Toolset) RegisterTools(s *server.MCPServer, prefix string) {

pkg/toolsets/toolsets.go:110

• [nitpick] The parameter name tool shadows the outer loop variable and may be confusing. Consider renaming it (e.g., to srvTool) to make the code clearer.

	registerToolWithPrefix := func(tool server.ServerTool) {