feat: Enhance volume indicators with ADOSC and SSF implementation and validation

lib/volume/adosc/Adosc.md

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+# ADOSC: Chaikin A/D Oscillator
+
+> "Momentum precedes price. Volume momentum precedes price momentum."
+
+The Chaikin Oscillator (ADOSC) is an indicator of an indicator. It applies the MACD formula to the Accumulation/Distribution Line (ADL) instead of the price.
+
+While the ADL is great for spotting long-term flow, it can be sluggish. ADOSC acts as a turbocharger, measuring the *momentum* of that flow. It anticipates changes in the ADL, often signaling a reversal before the ADL itself turns.
+
+## Historical Context
+
+Marc Chaikin created this oscillator because he found the standard ADL too slow for timing entries. He realized that applying the moving average convergence/divergence (MACD) logic to the ADL would highlight the acceleration and deceleration of buying pressure.
+
+## Architecture & Physics
+
+ADOSC is a derivative indicator. It depends on:
+
+1. **ADL**: The base volume flow metric.
+2. **EMA**: Two exponential moving averages of that metric.
+
+The physics here is identical to MACD:
+
+- **Fast EMA (3)**: Represents the immediate, short-term money flow.
+- **Slow EMA (10)**: Represents the established, medium-term money flow.
+- **Difference**: The spread between them represents the momentum of accumulation.
+
+### Zero-Allocation Design
+
+Our implementation composes existing zero-allocation components (`Adl` and `Ema`). The `Update` method simply pipes the bar into the ADL, and the ADL result into the two EMAs.
+
+## Mathematical Foundation
+
+$$
+ADOSC_t = EMA(ADL, 3)_t - EMA(ADL, 10)_t
+$$
+
+Where:
+
+- $ADL$ is the Accumulation/Distribution Line.
+- $EMA(X, N)$ is the Exponential Moving Average of X over N periods.
+
+## Performance Profile
+
+ADOSC is slightly heavier than ADL because it involves two EMAs.
+
+| Metric | Complexity | Notes |
+| :--- | :--- | :--- |
+| **Throughput** | ~15ns / bar | 1 ADL update + 2 EMA updates |
+| **Allocations** | 0 bytes | Hot path is allocation-free |
+| **Complexity** | O(1) | Constant time per update |
+| **Precision** | `double` | Required for EMA convergence |
+
+## Validation
+
+We validate against **TA-Lib**, **Skender.Stock.Indicators**, and **OoplesFinance**.
+
+- **Accuracy**: Matches external libraries to 9 decimal places.
+- **Note**: Tulip's `adosc` implementation diverges significantly from other libraries and is excluded from validation.
+
+### Common Pitfalls
+
+- **Volatility**: ADOSC is extremely volatile. It whipsaws frequently. It should never be used in isolation.
+- **Trend Confirmation**: Use it to confirm a trend, not to predict it. If price is rising but ADOSC is falling (divergence), the rally is running on fumes.
+- **Zero Line**: Crosses above zero indicate that short-term accumulation is overpowering long-term accumulation (Bullish). Crosses below zero indicate the opposite (Bearish).