Task: Solve this 4x4 Rush Hour puzzle - move car "C" from position [4,2] to the TARGET at position [2,4] given the position of the blockers below.

Current Grid State (JSON format):
[["H2","H2","H1","H1"],[".","B3",".","B1"],[".",".",".","."],["B2","C",".","."]]

Current Pieces:
- Car "C": Position [4,2]
- 1x1 Blockers (B1, B2, etc.): Single-cell obstacles that can be moved to clear a path
    - B3 at [2,2]
  - B1 at [2,4]
  - B2 at [4,1]
- 2x1 Blockers (H1, H2, etc.): Two-cell obstacles that move as a single unit
    - H2 (horizontal) at [1,1], [1,2]
  - H1 (horizontal) at [1,3], [1,4]
- TARGET: Position [2,4]

Movement Rules:
- Any piece (car "C", 1x1 blockers "B1, B2, etc.", or 2x1 blockers "H1, H2, etc.") can move UP, DOWN, LEFT, or RIGHT
- Each move is exactly ONE square in any direction for the entire piece
- For 2x1 blockers: The entire piece moves together as a unit (both cells move simultaneously)
- Pieces strictly CANNOT move outside the 4x4 grid
- Pieces strictly CANNOT move into occupied squares (i.e. squares that already have another piece)
- At ANY instant, there CANNOT be two pieces occupying the same square
- The same piece can move multiple times in a row if needed
- You win when car "C" reaches the TARGET cell

Coordinate System:
- Use [row,col] format where [1,1] is top-left, [4,4] is bottom-right
- Each cell shows its coordinates in black text: (row,col)
- For 2x1 blockers, both occupied cells are shown in the piece description

Expected Output Format:
Wrap your solution in <solution> tags and provide it as a numbered list of moves in this exact format:

<solution>
Step 1: [PIECE] [start_position] -> [end_position]
Step 2: [PIECE] [start_position] -> [end_position]
...
</solution>

For 1x1 pieces (car "C" and blockers "B1", "B2", etc.):
- Use single coordinate: C [2,1] -> [2,2]

For 2x1 pieces (blockers "H1", "H2", etc.):
- List both coordinates: H1 [[1,1],[1,2]] -> [[2,1],[2,2]]

Example response format:
<solution>
Step 1: B2 [3,2] -> [4,2]
Step 2: H1 [(2,3), (3,3)] -> [(1,3), (2,3)]
Step 3: B2 [2,4] -> [1,4]
Step 4: C [3,1] -> [3,2]
Step 5: C [3,2] -> [3,3]
Step 6: C [3,3] -> [3,4]
Step 7: C [3,4] -> [2,4]
</solution>