🔍 Implement pathfinding engine for format transformations

[szmyty]

Title: 🔍 Implement pathfinding engine for format transformations

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Description

Implement pathfinding over the transformation graph to determine optimal pipelines between formats.

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Goals

• compute transformation paths from input → target
• support cost-based and quality-aware optimization
• enable future multi-objective optimization

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Requirements

• implement pathfinding using Dijkstra or equivalent
• support weighted scoring:
  • cost (additive)
  • quality (multiplicative)
• compute total path cost and total path quality
• return ordered list of transforms for a valid path
• support evaluation of multiple candidate paths

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Acceptance Criteria

• pathfinding returns valid paths between formats
• scoring accounts for cost and quality
• total path metrics are calculated correctly
• multiple paths can be evaluated if needed
• code compiles successfully