Fix MC nested-dataclass round-trip; add CI + vesting-curve test

[Pattermesh]

What

• Fix a real bug in the Monte Carlo config round-trip. On a clean clone, 4 tests in tests/test_monte_carlo.py failed with AttributeError: 'dict' object has no attribute 'volume_usd_m0': _dict_to_config / _dict_to_dataclass left revenue_streams and vest_buckets as plain dicts, so run() crashed.
  • Root cause 1: _dict_to_config inferred the list element type from a default SimConfig(), whose list fields are empty (field(default_factory=list)), so the reconstruction branch was dead code.
  • Root cause 2: _dict_to_dataclass did cls() with no args, which raises for dataclasses with required positional fields (RevenueStream, VestBucket).
  • Fix: declare the nested-list-field → dataclass mapping explicitly, and build instances directly from matching dict fields.
• Add CI (.github/workflows/ci.yml): installs the package with dev extras and runs pytest -q on Python 3.10, 3.11, 3.12, on push to main and on PRs. No workflow existed before.
• Add one meaningful test for the vesting-curve model path (test_vesting_curve_respects_cliff_and_unlocks_full_allocation): asserts supply stays flat through the cliff, then exactly fraction_of_supply * total_supply is released linearly over the unlock window with no overshoot. Mutation-checked: it fails if the cliff logic is removed.

Verification

Clean clone + pip install -e ".[dev]" + pytest -q:

...................                                                      [100%]
19 passed in 0.41s

(18 pre-existing tests, previously 4 failing on a clean clone, plus the 1 new vesting-curve test.)

🤖 Generated with Claude Code

[abhicris]

Welcome to kcolbchain, @Pattermesh — glad you're here. 🌱

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