Include CAPI deps for global function types

[justjavac]

Fixes #4123.

Summary:

• Add CAPI include discovery for CEF pointer types used by global function return values and arguments.
• Apply the same behavior to versioned CAPI headers.
• Add regression coverage for cef_process_util.h including cef_command_line CAPI dependencies.

Testing:

• python3 tools/make_capi_header_test.py
• Verified full-header generation for cef_process_util.h includes cef_command_line_capi.h and cef_command_line_capi_versions.h

[magreenblatt]

Thanks, this PR looks good.