OCI Database Cloud Services : Skills for ExaDB-XS Worflow

[Kushal34563]

Description:
This PR adds a comprehensive ExaDB-XS skill for managing Oracle Exadata Database Service on Exascale Infrastructure through OCI MCP operations.

The skill supports the full ExaDB-XS resource hierarchy:

• Exascale DB Storage Vaults
• ExaDB VM Clusters
• DB Homes
• Databases/CDBs
• Pluggable Databases/PDBs

Key capabilities include:

• Guided collection of required and optional parameters.
• No mutation calls allowed
• Hierarchy-aware inspect, and list flows.
• OCI MCP operations through oracle/mcp oci-api-mcp-server.
• GI major-version and minor-version discovery guidance.
• Safe handling of passwords, private keys, and other sensitive values.
• Clear boundaries for compartments, subnets, NSGs, and other external dependencies.
• Guardrails against unsupported service families, invented values, unsafe destructive actions.

The skill is organized around a central workflow guide, OCI MCP references, and service metadata.