BoltzInput use gemmi.one_letter_code for consistent with boltz

[0ut0fcontrol]

Example 1abi:

$ pxm gen-input -i 1abi.cif -it cif -o 1abi.yaml -ot boltz
2025-12-17 10:57:50,452 - WARNING - Change DPN->F to DPN->X for consistent with boltz (use gemmi.one_letter_code).
2025-12-17 10:57:50,452 - WARNING - Change DPN->F to DPN->X for consistent with boltz (use gemmi.one_letter_code).
2025-12-17 10:57:50,452 - WARNING - Change HMR->R to HMR->X for consistent with boltz (use gemmi.one_letter_code).
2025-12-17 10:57:50,487 - INFO - Generated 1abi.yaml from 1abi.cif

$ cat 1abi.yaml 
sequences:
- protein:
    id: A
    sequence: TFGSGEADCGLRPLFEKKSLEDKTERELLESYIDGR
- protein:
    id: B
    sequence: IVEGSDAEIGMSPWQVMLFRKSPQELLCGASLISDRWVLTAAHCLLYPPWDKNFTENDLLVRIGKHSRTRYERNIEKISMLEKIYIHPRYNWRENLDRDIALMKLKKPVAFSDYIHPVCLPDRETAASLLQAGYKGRVTGWGNLKETWTANVGKGQPSVLQVVNLPIVERPVCKDSTRIRITDNMFCAGYKPDEGKRGDACEGDSGGPFVMKSPFNNRWYQMGIVSWGEGCDRDGKYGFYTHVFRLKKWIQKVIDQFGE
- protein:
    id: C
    modifications:
    - ccd: DPN
      position: 1
    - ccd: DPN
      position: 12
    - ccd: HMR
      position: 3
    sequence: XPXGGGGGNGDXEEIPEEYL

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