feat: expose MCP-compatible Bedrock dataset endpoints via LSP DataSet service

[Copilot]

This change adds MCP-style Bedrock dataset endpoints to the LSP so AI tooling can query live workspace and vanilla data through a consistent protocol surface. It introduces support for project entities/blocks and vanilla command identifiers.

• Shared protocol additions (DataSets)

  • Added MCP endpoint identifiers:
    • bedrock://project/entities
    • bedrock://project/blocks
    • bedrock://vanilla/commands

• LSP dataset routing

  • Extended DataSetService request resolution to map MCP endpoints to existing data sources:
    • bedrock://project/entities → workspace resource summaries (entities)
    • bedrock://project/blocks → workspace resource summaries (blocks)
    • bedrock://vanilla/commands → vanilla command ids (CommandData.VanillaCommands)
  • Reused existing dataset id filtering behavior for MCP project endpoints.

• Focused coverage

  • Added dataset/service.test.ts cases for:
    • MCP project entities resolution
    • MCP project blocks resolution with id filtering
    • MCP vanilla commands resolution

switch (datatype) {
  case DataSets.MCP.Project.Entities:
    return projectData ? getWorkspaceResourceSummaries(projectData, 'entities') : undefined;
  case DataSets.MCP.Project.Blocks:
    return projectData ? getWorkspaceResourceSummaries(projectData, 'blocks') : undefined;
  case DataSets.MCP.Vanilla.Commands:
    return CommandData.VanillaCommands;
}