Raise JsonPatchConflict instead of TypeError on invalid move/copy/remove targets

[eeshsaxena]

Some patches make apply_patch raise a bare TypeError instead of a JsonPatchConflict:

import jsonpatch
jsonpatch.apply_patch([1, 2, 3], [{'op': 'copy', 'path': '/0', 'from': '/-'}])
# TypeError: list indices must be integers or slices, not str
jsonpatch.apply_patch({'foo': 'bar'}, [{'op': 'remove', 'path': '/foo/0'}])
# TypeError: 'str' object doesn't support item deletion

move/copy read subobj[part] from the from pointer and remove does del subobj[part]. When the pointer ends in - (the array-append token), part is the string '-' used to index a list; when it points into a string value the container is immutable. Both raise TypeError, which isn't in the except (KeyError, IndexError) clauses. I added TypeError to those three clauses so the operations report JsonPatchConflict like other invalid targets. Valid moves/copies/removes are unaffected.

Added three tests to ConflictTests; they raise TypeError on master and pass with the change, and the full suite still passes. Found it by fuzzing apply_patch with random patches.

[Copilot]

Pull request overview

This PR improves error consistency in apply_patch by ensuring invalid move/copy/remove targets raise JsonPatchConflict instead of leaking bare TypeError, aligning these operations with how other invalid-pointer scenarios are reported in the library.

Changes:

• Catch TypeError in RemoveOperation, MoveOperation, and CopyOperation when indexing/deleting with invalid targets and re-raise as JsonPatchConflict.
• Add regression tests covering from: "/-" for copy/move and removing through a pointer into a string value.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
jsonpatch.py	Expands exception handling for remove/move/copy to convert certain TypeErrors into JsonPatchConflict.
tests.py	Adds regression tests ensuring these invalid targets raise JsonPatchConflict rather than TypeError.

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[eeshsaxena]

Hi! Gentle nudge on this one whenever you have some bandwidth. It's a small, self-contained fix (Raise JsonPatchConflict instead of TypeError on invalid move/copy/remove targets), and it's currently mergeable with no conflicts. No urgency at all, and I'm happy to make any changes you'd like. Thanks for maintaining python-json-patch!