Add OCI IoT gateway-aware MCP support

[wsanders00]

Description

Adds gateway-aware OCI IoT MCP support for src/oci-iot-mcp-server.

Fixes #347

Supersedes the closed, unmerged PR #348 with an updated and independently reviewed commit.

This change:

• Preserves and accepts gateway-aware digital twin instance fields, including connectivity_type and gateways.
• Adds topology and readiness helpers for gateway-aware twin workflows.
• Reports unresolved topology warnings as readiness warnings while preserving gateway counts, child counts, and warning details.
• Adds bounded relationship pagination and SDK-parity filters for OCI IoT list tools.
• Preserves additional OCI SDK fields in mapped digital twin and relationship responses.
• Updates the OCI IoT MCP documentation and regression coverage.
• Refreshes compatible OCI IoT MCP dependencies, including OCI Python SDK 2.180.0.

No breaking MCP interface changes are included.

Type of change

• 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 not to work as expected)
• This change requires a documentation update

How Has This Been Tested?

• make test project=oci-iot-mcp-server
• make lint
• make lock-check project=oci-iot-mcp-server
• git diff --check

Test result summary:

• 311 tests passed.
• OCI IoT MCP package coverage: 91.93%.
• Combined coverage: 92%.
• Lint, lock consistency, and diff checks passed.
• Dependency resolution found no compatible package-version updates. Current uv proposes only unrelated secretstorage marker normalization, which was not included.
• pip-audit reports the existing cryptography 46.0.7 advisory, GHSA-537c-gmf6-5ccf. The OCI SDK currently requires cryptography<47.0.0, while the advisory is fixed in 48.0.1. The MCP code does not directly expose arbitrary ASN.1 parsing, and upstream main already locks the same version.

The final review fixes have deterministic unit coverage and do not require live OCI mutations.

Test Configuration:

• Firmware version: N/A
• Hardware: N/A
• Toolchain: Python 3.13.9, uv, pytest 9.1.1
• SDK: OCI Python SDK 2.180.0

Checklist

• My code follows the style guidelines of this project.
• I have performed a self-review of my own code.
• I have commented code where additional explanation is needed.
• I have made corresponding documentation changes.
• My changes generate no new warnings.
• I have added tests that prove the changes are effective.
• New and existing unit tests pass locally.
• There are no unpublished dependent changes.