fix(document-understanding): align OCI SDK and FastMCP dependencies

[dustin-sale]

Description

Fix locked dependency sync for Document Understanding by pinning OCI SDK to
2.185.0, matching oracle-mcp-common's minimum, and requiring FastMCP

=3.4.5,<4.0.0.

Refresh vulnerable locked dependencies to address 20 Dependabot alerts:
PyJWT 2.15.1, urllib3 2.8.0, cryptography 50.0.2, and compatible
PyOpenSSL 26.4.0.

Review OCI SDK compatibility and add a test that builds extraction and
classification requests with real SDK models. Update the changelog with
dependency, security, and platform compatibility changes.

The cryptography update removes upstream support for Intel macOS and
32-bit Windows.

Type of change

• Breaking change: dependency security updates remove upstream support
  for Intel macOS and 32-bit Windows.

How Has This Been Tested?

• Original locked sync command succeeds.
• 52 server tests pass with 93.99% coverage.
• 7 FastMCP tool tests pass with minimum version 3.4.5.
• Lock check, source/wheel build, and install check pass.
• pip-audit reports zero known vulnerabilities across 86 packages.
• Updated versions fall outside all 20 reported vulnerable ranges.
• Local OCI API-key/security-token request signing and RS256 JWT
  encode/decode pass.

Tested on macOS ARM64 with Python 3.14.7, OCI SDK 2.185.0, and FastMCP
3.4.7. Live OCI requests were not run.

Checklist

• Changes follow project style guidelines.
• Completed self-review.
• Updated the changelog.
• Added SDK compatibility test coverage.
• New and existing unit tests pass locally.