feat(bigtable): add prebuilt source and tools configuration (--prebuilt bigtable)

Prerequisites

• Search the current open issues

What are you trying to do that currently feels hard or impossible?

Users who want to use MCP Toolbox with Google Cloud Bigtable currently have to manually author a tools.yaml configuration defining the bigtable source and each individual admin, schema discovery, and SQL tool. Providing an out-of-the-box --prebuilt bigtable configuration allows users to immediately inspect instances, clusters, tables, views, schemas, and execute SQL queries without writing boilerplate YAML.

Suggested Solution(s)

Add a prebuilt configuration file (internal/prebuiltconfigs/tools/bigtable.yaml) and documentation (docs/en/integrations/bigtable/prebuilt-configs/bigtable.md) that:

Configures a bigtable-source parameterized by environment variable (BIGTABLE_PROJECT). Includes all 27 Bigtable tools (instance/cluster/table/view lifecycle management, schema inspection, and execute_sql). Organizes the tools into 3 logical tool groups (admin, data, views), each with < 10 tools to follow Toolbox best practices for LLM context limits:

--prebuilt bigtable (loads all 27 tools) --prebuilt bigtable/admin (10 instance & cluster admin tools) --prebuilt bigtable/data (9 table admin, schema discovery, & SQL tools) --prebuilt bigtable/views (8 logical & materialized view tools)

Alternatives Considered

Manually creating and maintaining a custom tools.yaml file for Bigtable.

Additional Details

No response