[tylrcc]

Closes #16.

Python port of the AdjointAmericanEquityOption C++ example, following the pattern of swap-adjoint.py:

• Same setup as the C++ original: American put, spot 36, strike 40, rate 0.06, vol 0.20, dividend yield 0.00, evaluation date 15 May 1998, maturity 17 May 1999, priced with FdBlackScholesVanillaEngine (801 time steps, 800 grid points).
• All five inputs registered on the tape; rho, strike sensitivity, vega, delta, and dividend rho from a single adjoint pass.
• The example cross-checks the Greeks against bump-and-reprice finite differences (eps = 1e-5).

Testing: the current QuantLibAAD wheel is not reachable from my sandbox, so I ran the identical example code against QuantLib-Risks 1.33.3 (the direct predecessor of QuantLibAAD; only the tape-construction lines differ between the two APIs). It runs end to end: value 4.4861132726; rho adjoint -10.342487 vs bump -10.341887; strike 0.739227 vs 0.739227; vega 10.936834 vs 10.937061; delta -0.696749 vs -0.696749.

One known mismatch, documented in the example itself: the FD engine builds its operator from the dividend yield as a plain value, so the adjoint dividend rho comes out numerically zero (0.000031) while bumping gives 9.046635. I verified this is specific to the FD engine, not the port: the analytic engine and Barone-Adesi-Whaley both produce dividend rhos that match bumping on the same setup, and the FD engine shows the same behaviour for a European option. The C++ example has the same property, since it uses the same engine. Flagging it here in case you would rather the example note be worded differently.

Note: this repo requires a signed CLA before merge (per CONTRIBUTING) — I understand it will be handled through the CLA flow.

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