fix: preserve representable 0.01-lot grid points in money sizing

[luisleo526]

Division by binary64 0.01 could floor a quantity one lot below a grid point that the input already represents. The money-sizing helper now checks an exact scale-of-100 candidate and accepts it only when the reconstructed grid quantity does not exceed the input. This adds no epsilon and preserves the existing under-floor controls and other lot sizes.

Validated on engine a03ac6d3fb42df5af1db9e39727daf450b2fb71f with codegen 3fd97fe28abd7b191cb376d9f5db4e056fcfae4b:

• Cloud Run measured all 4,190 probes in 72/72 cases. SERHAN1 EURUSD moves from strong to excellent: canonical count difference 1 to 0 and match 99.8% to 100%. The other 4,189 canonical results are unchanged, with zero regressions, errors or gaps. Result: 4,164 excellent / 26 strong / zero moderate.
• The target matches TradingView on side, time, price and quantity for 2,219 of 2,220 entry/exit rows. Only the existing final range-end price mark differs; the missed close, re-entry and subsequent quantities are restored.
• Gate pineforge-pr-gate-h59tq: PASS, target score +1, and zero regressions or tolerated exceptions across 704 hard probes.
• Fresh build and 214/214 tests passed, including the existing money-precision and band controls. Covered TradingView quantity and capital controls confirm the boundary. Independent Grok 4.6 review of this exact candidate is GREEN, P0/P1/P2 = 0.

Grading metrics, thresholds, tolerances, verifier, harness, tapes and population are unchanged. An unconditional scale-of-100 version was rejected because it broke an existing TradingView control; the guarded version preserves that control.

Candidate snapshot: f9f708d622270b207b1234b8f8031a237a3499391a29e6377233c3d5d90bfc9b (788,855 bytes).