docs: replace deprecated code_interpreter/local_code_interpreter with python_tool()

[AngeloDanducci]

code_interpreter() and local_code_interpreter() were deprecated in favour of python_tool(). Several examples and docs pages still reference the old functions, producing DeprecationWarning at runtime.

Deprecation mapping

Old	New
code_interpreter(code)	python_tool(tier='docker_unsafe').run(code=code)
local_code_interpreter(code)	python_tool(tier='local_unsafe').run(code=code)
MelleaTool.from_callable(local_code_inter…)	python_tool(tier='local_unsafe')
uses_tool(local_code_interpreter)	uses_tool(python_tool(tier='local_unsafe'))
result.tool_calls["local_code_interpreter"]	result.tool_calls["python_tool"]

Note: python_tool() returns a MelleaTool directly, so MelleaTool.from_callable() wrapping is no longer needed.

Files to update

• docs/examples/tools/interpreter_example.py — lines 7, 12, 23, 35, 37, 45, 49, 62, 65, 74, 82, 86
• docs/examples/tools/README.md — lines 11, 53, 56, 65, 70, 78, 82–83, 88, 92, 99, 104, 107, 112, 120–121, 161
• docs/docs/how-to/tools-and-agents.md — lines 114, 119–120, 129–130, 146, 152, 155, 162, 264, 266, 270, 274

Additional context

• Deprecation warning observed while running the README snippet smoke tests in Bug: Tool examples broken after PR #380 - need MelleaTool wrapper #383
• python_tool() requires an explicit tier argument; omitting it raises a warning. Use tier='local_unsafe' for local execution (replaces local_code_interpreter) and tier='docker_unsafe' for sandboxed execution (replaces code_interpreter)
• The tool name exposed to the LLM changes from "local_code_interpreter" / "code_interpreter" to "python_tool" — .tool_calls key lookups in examples need updating accordingly