message: docs: add 0/1-indexing hints to input-files.md
diff: @@ -95,6 +95,8 @@ Accepted formats: JSON. Example configuration for SARS-CoV-2:
  }
  ```
  +Note that the positions are 0-indexed and codon range ends are excluded. So `ORF3a:257-276` should be encoded as `{"begin": 256, "end": 276 }`.
  +
  ## Gene map
  (or "genome annotations")
  @@ -196,6 +198,8 @@ It is of the following schema (shortened for clarity):
  }
  ```
  +Positions are 1-indexed.
  +
  Nextclade Web (advanced mode): accepted in "Virus properties" drag & drop box.
  Nextclade CLI flag: `--input-virus-properties`
  