Validate model names in explicit XML node syntax

[Vryuz]

Explicit node syntax currently bypasses model-name validation: a registered ID such as <Action ID="Node.With.Dot"/> is accepted even though compact syntax rejects the same model name. Validate the resolved lookup name for both forms, including Action, Condition, Decorator and Control wrappers.

Fixes #1220.

This changes XML parsing behavior for explicit IDs that violate the documented model-name rules. Valid ASCII/Unicode IDs and relaxed instance names remain supported; programmatic registration and the public API/ABI are unchanged.

Validation:

• The regression fails on the original parser and passes with the fix; all 28 name-validation tests pass.
• Tests cover registered invalid IDs with specific diagnostics, all four wrappers, underscore/hyphen/digit-leading/Unicode IDs, and relaxed instance names.
• Repository pre-commit hooks pass for both changed files.
• Full Release CTest suite: 538 passed, 2 locale-dependent tests skipped, 0 failed (540 registered).
• Repository-wide ./run_clang_tidy.sh passes with clangd-21.