[Ashu-t021]

Closes #73

Summary of changes

• Updated _search in src/dkit/commands/errors.py to use .casefold() for case-insensitive matching across error types, codes, and descriptions.
• Updated CLI option help text and description string in src/dkit/commands/errors.py to reflect case-insensitivity.
• Updated test assertions in tests/test_errors.py to test case-insensitive search behavior.
• Verified 100% line and branch test coverage for errors.py.
• Updated CHANGELOG.md under [Unreleased].
• Formatted and linted with Ruff.

[Bytewave1]

Thanks @Ashu-t021, the fix itself is correct: I checked --search missing, Missing and MISSING (3 results each), HTTP, 5XX and an empty search (still exit 2). Tests are green with 100 % coverage and ruff is clean.

I ran mutation tests on _search and some mutations survive, which means a few ways to break the behaviour are not covered yet:

• only lower-casing the search text but not the searched text (so --search missing would no longer find "Missing access")
• applying casefold() to only some of the fields (type, code, description), not all three
• echoing a changed query in the JSON output

Please add this test (or an equivalent one) to tests/test_errors.py:

def test_cli_errors_search_ignores_case_in_every_field(cli) -> None:
    # description: "Missing access" is stored with a capital M
    missing = cli("--json", "errors", "--search", "missing").json
    assert "50001" in [entry["code"] for entry in missing["error_codes"]]
    # type: stored in lower case, and 404 does not contain "http" in its text
    http = cli("--json", "errors", "--search", "HTTP").json
    assert "404" in [entry["code"] for entry in http["error_codes"]]
    # code: stored as "5xx"
    five = cli("--json", "errors", "--search", "5XX").json
    assert "5xx" in [entry["code"] for entry in five["error_codes"]]
    # the query is echoed as typed
    assert five["query"] == "5XX"

Small CHANGELOG fixes: there is trailing whitespace on the new bullet (git diff --check reports it), and the other blocks have an empty line between the ### Changed heading and the first bullet. Please also end the bullet like the others, for example:

[Ashu-t021]

Thanks for the review! I've added the mutation test covering all three fields and query echoing to tests/test_errors.py, cleaned up the trailing whitespace, and formatted the entry under ### Changed in CHANGELOG.md.

[Bytewave1]

Thanks, this looks good. --search is now case-insensitive across type, code and description, the tests cover each field, and the changelog entry is in the right place.

[Bytewave1]

Thanks @Ashu-t021, merged! This also fixes #73. Nice work on picking up the review notes so quickly.