Regenerate API docs; add threading note to reference intro

Add a one-line threading-contract note to the API reference intro (HTML +
Markdown generators) and regenerate all documentation artifacts (HTML,
Markdown, man page, type stubs) to pick up the updated mcrfpy.lock() docstring.

Refs #327

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tools/generate_dynamic_docs.py

@@ -369,7 +369,8 @@ def generate_html_docs():
         <h1>McRogueFace API Reference</h1>
         <p><em>Generated on {datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')}</em></p>
         <p><em>This documentation was dynamically generated from the compiled module.</em></p>
-        
+        <p><strong>Threading:</strong> any access to mcrfpy objects from a non-main thread must happen inside <code>with mcrfpy.lock():</code>; behavior outside the lock is undefined. See <a href="threading-model.md">docs/threading-model.md</a>.</p>
+
         <div class="toc">
             <h2>Table of Contents</h2>
             <ul>
@@ -517,6 +518,8 @@ def generate_markdown_docs():
 
 *This documentation was dynamically generated from the compiled module.*
 
+**Threading:** any access to mcrfpy objects from a non-main thread must happen inside `with mcrfpy.lock():`; behavior outside the lock is undefined. See [docs/threading-model.md](threading-model.md).
+
 ## Table of Contents
 
 - [Functions](#functions)