Function process_pads 

pub fn process_pads(directives: &[Directive]) -> PadResult

Process pad directives and generate synthetic transactions.

This function:

1. Tracks account inventories
2. When a pad is encountered, stores it as pending
3. When a balance assertion is encountered for an account with a pending pad, generates a synthetic transaction to make the balance match
4. Returns the directives with synthetic transactions inserted

Arguments

• directives - The directives to process (should be sorted by date)

Returns

A PadResult containing:

• The original directives (with pads preserved for reference)
• Synthetic padding transactions
• Any errors encountered