Fix non-ASCII characters in external items and external file descriptors

[yutaro-sakamoto]

This pull request fixes the following bugs related to non-ASCII characters.

• The older version does not convert － in external items and external file descriptors into another valid character in Java.
• The older version converts ＢＣ in external file descriptors into invalid characters.

Addition of a new test case:

• Added a new test in tests/misc.src/fd-external.at to verify the handling of external file descriptors with non-ASCII characters in field names.

[Copilot]

Pull Request Overview

This pull request addresses bugs related to non-ASCII character handling in external items and file handlers by replacing manual string conversion loops with dedicated helper functions. Key changes include:

• Replacing manual '-' replacement with a call to strcpy_identifier_cobol_to_java.
• Removing in-line conversion loops in external file handler routines.
• Updating external item declarations to use consistent helper functions for identifier conversion.

Files not reviewed (1)

• tests/misc.src/fd-external.at: Language not supported

Comments suppressed due to low confidence (2)

cobj/codegen.c:2255

• [nitpick] Verify that passing 'CB_FILE(file)->record->name' directly produces the correct identifier conversion without the previously used manual loop, especially for non-ASCII characters.

joutput(" = CobolExternal.getStorageAddress ("%s", %d);",

cobj/codegen.c:5581

• [nitpick] Confirm that the combined use of joutput_prefix() and joutput_base(f) fully replicates the intended transformation behavior for external item names, ensuring correct handling of non-ASCII characters.

joutput_prefix();