Add Common OCI Client Library and Update user-agent

[cboffa13]

Description

These changes add a common library which can be shared across many mcp servers. Notably this library exports a decorator called @with_oci_client which automatically configures a client based on the SDK client class given so we dont need the get_identity_client, get_compute_client etc... functions. Additionally it adds the mcp server tool's name to the user_agent header for tracking in the format of server/version (tool_name)

Fixes # (issue) - TBD

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

• You should be able to use the all of the existing features of any oci-specific server without any loss of functionality
• The mcp tool name should be included in the request header: server/version (tool_name)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[cboffa13]

Things still need to be done

• Test all the servers
• Add change to oci-cloud-mcp
• Add change to oci-api-mcp
• add change to oci-database-mcp-server