fix(inference): fail when an input glob matches no files

[kevin9327]

Problem

-i/--input-files accepts glob patterns (inputs/*.json). _from_files already rejects an empty input list, and a literal path that doesn't exist raises FileNotFoundError. A pattern that matches nothing, though, expands to an empty list and is silently dropped:

from_files(Sample, [d / "*.json"])    # [Sample(name='a')]
from_files(Sample, [d / "*.jsn"])     # []                  <- typo, no error
from_files(Sample, [d / "nope.json"]) # FileNotFoundError

In scripts/inference.py (lines 43–72) that empty list flows on. The script logs Loaded 0 samples, builds the pipeline (loading the checkpoint), calls generate([]) and exits normally without generating anything. When several patterns are passed and only one has a typo, that pattern's samples just go missing from the run. inference/ray/submit.py, inference/ray/gradio.py and scripts/upsample_prompts.py load inputs through the same function.

Fix

When a glob pattern matches no file, raise ValueError("No inference parameter files match '<pattern>'"), in line with the existing empty-list and missing-path errors. Literal paths and patterns that do match are unchanged.

Tests

Added to cosmos_framework/inference/common/args_test.py:

• test_from_files_expands_glob_patterns: a matching pattern loads every match (sorted), and a missing literal path still raises FileNotFoundError. Passes both before and after the change, so the check only adds the no-match case.
• test_from_files_raises_when_a_glob_matches_nothing: a non-matching pattern raises, including when it sits next to a matching one.

Fail-before (source reverted, tests kept):

_____________ test_from_files_raises_when_a_glob_matches_nothing ______________
cosmos_framework/inference/common/args_test.py:46: in test_from_files_raises_when_a_glob_matches_nothing
    with pytest.raises(ValueError, match=r"No inference parameter files match"):
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
E   Failed: DID NOT RAISE ValueError

Counts for args_test.py:

	passed	failed
main, existing tests	10	2
new tests, source reverted	11	3
new tests, with fix	12	2

The 2 failures present in every row come from my environment (Windows, CPU) and fail the same way on main: test_download_file needs symlink privilege, and test_parse_checkpoint_path builds a path longer than MAX_PATH.

Run on CPU: PYTHONUTF8=1 COSMOS_TRAINING=0 pytest cosmos_framework/inference/common/args_test.py.

Lint

ruff 0.12.7 (repo pin): ruff check passes on both touched files before and after. ruff format --diff is the same size before and after for each file (3 and 4 lines, pre-existing).

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