strategies.py: strategy_features() silently accepts any unrecognized strategy name

[yakew7]

Where: faircode/strategies.py:97-102 (strategy_features).

The gap:

def strategy_features(strategy: str, core: list, proxies: list, protected: list) -> list:
    if strategy == "baseline":
        return list(dict.fromkeys(core + proxies + protected))
    if strategy == "unawareness":
        return list(dict.fromkeys(core + proxies))
    return list(core)  # unawareness_proxy_removal, in_processing, post_processing

The final return list(core) is a bare else in practice - it's meant to handle exactly the three strategies named in its comment, but any unrecognized string (a typo like "in_procesing") silently falls into the same branch instead of raising.

Repro:

>>> from faircode.strategies import strategy_features
>>> strategy_features("in_procesing", ["a"], ["b"], ["c"])   # typo'd
['a']

No error - returns exactly the same result as a genuinely recognized "core-only" strategy.

Why it matters: faircode/benchmark.py only ever iterates the fixed STRATEGIES tuple today, so this isn't reachable through the CLI/normal benchmark run - but strategy_features is a public-enough function (imported directly, no leading underscore) that anyone calling it from a notebook, script, or future extension gets a silent wrong-but-plausible answer for a typo'd strategy name instead of an error. tests/test_strategies.py has no "unknown strategy" test.

Suggested fix: add an explicit else: raise ValueError(f"unknown strategy: {strategy!r}") instead of the bare fallback.