DSL parser in Tela (JSX) for graph-boxes renderer

[theuseless-ai]

Goal: Replace the hardcoded NODES/EDGES arrays in graph-boxes with a DSL text parser, so the renderer can visualize any workflow from DSL input.

Context: The graph-boxes example currently has hardcoded demo data. For production use, it needs to consume DSL text (or JSON from the API) and render any workflow topology. The DSL parser here is the Rust/JSX-side counterpart to the Python parser in Pipelit.

Acceptance Criteria:

• JSX-side parser: DSL text → NODES + EDGES arrays
• Also accepts JSON (API response format) as input
• Auto-layout algorithm: positions nodes based on topology (no manual x/y)
• Handles: linear chains, branches (switch/fork), loops, sub-workflows
• Handles: variable-height agent nodes (expanded with sub-items)
• Tested with 5+ different workflow topologies
• graph-boxes example updated to load from DSL file instead of hardcoded data

Dependencies: DSL format spec (Pipelit #163)

Priority: P1 (required for graph TUI)