docs: refresh stale "Phase 1" docstring in mm_config (#135)

The module-level docstring still described mm_config as Phase 1 with
four sub-configs, but Phases 2–3 (PRs #129, #130, #131) and the
auto-exclude work (PR #132) added six more groups. Rewrite the opening
paragraph so it reflects the current set without naming a specific
phase that will keep going stale.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: keitaj

strategies/mm_config.py

@@ -1,9 +1,10 @@
 """Configuration dataclasses for ``MarketMakingStrategy``.
 
-Phase 1 of the MM config refactor: groups four sets of related parameters
-(loss-streak cooldown, micro-price skew, BBO velocity guard, per-coin
-overrides) into dataclasses and exposes a :meth:`MMConfig.from_legacy_dict`
-constructor for the existing flat ``strategy_config`` dict.
+Groups related MM parameters into sub-config dataclasses (loss-streak,
+micro-price, velocity guard, per-coin overrides, imbalance, close,
+schedule, dynamic offset, dynamic age, auto-exclude) under :class:`MMConfig`,
+and exposes :meth:`MMConfig.from_legacy_dict` to build it from the existing
+flat ``strategy_config`` dict.
 
 This module also defines a handful of constants for values that were
 historically read via ``config.get`` but never exposed via CLI/env. They