feat(add stenography doc):

docs/stenography.md

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+# Stenography Functions
+
+The stenography module provides various text obfuscation and transformation techniques for security testing. This document explains its architecture and implementation.
+
+## Overview
+
+The module implements:
+
+1. Rotation ciphers (ROT13, ROT5)
+1. Base64 encoding
+1. Text manipulation functions
+1. Randomization techniques
+1. Character substitution methods
+
+## Core Functions
+
+### Rotation Ciphers
+
+```python
+def rot13(input_text):
+    """
+    Applies ROT13 cipher to input text
+    - Preserves case of letters
+    - Leaves non-alphabetic characters unchanged
+    """
+    # Implementation details...
+
+def rot5(input_text):
+    """
+    Applies ROT5 cipher to input text
+    - Rotates digits by 5 positions
+    - Leaves non-digit characters unchanged
+    """
+    # Implementation details...
+```
+
+### Encoding
+
+```python
+def base64_encode(data):
+    """
+    Encodes input data using Base64
+    - Handles both string and bytes input
+    - Returns UTF-8 encoded string
+    """
+    # Implementation details...
+```
+
+### Text Manipulation
+
+```python
+def mirror_words(text):
+    """
+    Reverses each word in the input text
+    - Preserves word order
+    - Maintains spaces between words
+    """
+    # Implementation details...
+
+def scramble_words(text):
+    """
+    Randomly scrambles middle letters of words
+    - Preserves first and last letters
+    - Handles words shorter than 4 characters
+    """
+    # Implementation details...
+```
+
+### Randomization
+
+```python
+def randomize_letter_case(text):
+    """
+    Randomly changes case of each character
+    - Independent case changes per character
+    - Preserves non-letter characters
+    """
+    # Implementation details...
+
+def insert_noise_characters(text, frequency=0.2):
+    """
+    Inserts random characters between existing ones
+    - Configurable insertion frequency
+    - Uses alphanumeric characters for noise
+    """
+    # Implementation details...
+```
+
+### Advanced Transformations
+
+```python
+def substitute_with_ascii(text):
+    """
+    Replaces characters with their ASCII codes
+    - Space-separated numeric values
+    - Preserves original character order
+    """
+    # Implementation details...
+
+def remove_vowels(text):
+    """
+    Removes all vowel characters from text
+    - Handles both lowercase and uppercase vowels
+    - Preserves non-vowel characters
+    """
+    # Implementation details...
+
+def zigzag_obfuscation(text):
+    """
+    Alternates character case in zigzag pattern
+    - Starts with uppercase
+    - Toggles case for each alphabetic character
+    """
+    # Implementation details...
+```
+
+## Usage Patterns
+
+1. **Text Obfuscation**:
+
+   ```python
+   obfuscated = zigzag_obfuscation(
+       scramble_words(
+           insert_noise_characters(text)
+       )
+   )
+   ```
+
+1. **Encoding**:
+
+   ```python
+   encoded = base64_encode(rot13(text))
+   ```
+
+1. **Randomization**:
+
+   ```python
+   randomized = randomize_letter_case(
+       remove_vowels(text)
+   )
+   ```
+
+## Configuration
+
+- **Noise Frequency**: Configurable in insert_noise_characters()
+- **Scrambling**: Automatic handling of word lengths
+- **Case Handling**: Preserved in rotation ciphers
+
+## Limitations
+
+- Primarily handles ASCII text
+- Limited to implemented transformation types
+- Randomization is not cryptographically secure