[openhuman#7523] tinytools: take over status, timeout, policy engine and tool-result classification from OpenHuman core #65

Context: master epic tinyhumansai/openhuman#7523 (minimal openhuman-core) moves generic tool code out of crates/openhuman-core/src/tools into this repo. Dependency epic: tinyhumansai/openhuman#7541. tinytools is a kernel library (nested at vendor/tinyagents/vendor/tinytools), not a loadable module. After merge: tinyagents PR bumping its tinytools gitlink, then OpenHuman pins vendor/tinyagents.

• tinytools::status module: move classify, ClassifiedFailure, failure types and generic constants (e.g. MODULE_FAULT_MARKER) from tools/status/{ops,types}.rs, with their tests; fixture classifications unchanged (openhuman#7623)
• tinytools-std::timeout: move process_cleanup, group_exit, command_environment and add configure(settings) over the existing ToolTimeoutSettings; unix regression test that a sleeping child group is reaped on timeout (openhuman#7624)
• tinytools: add tool-policy profiling/engine (agent_policy/{engine,prompt,types}), registry vocabulary (registry/types, registry/denials) and the host half of ToolExposure::Deferred (meta/deferred), with tests; coordinate with openhuman#7328 / tinyagents-harness policy_gate placement (openhuman#7627)
• tinytools-std: add web_fetch::status_of (from fetched_site.rs) and fs::is_read_only_call (from tool_output_file_read.rs) with tests (openhuman#7628)