Refine comments in unittest.yml for clarity

Updated comments to clarify test case categorization and resource management in CI/CD.

Author: bact

.github/workflows/unittest.yml

@@ -32,28 +32,12 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        # To save time and resources, and manage dependency compatibility,
-        # we divide test cases into 3 groups
-        # and run them in different configurations:
-        # - Core    (O): All supported Python versions on Ubuntu,
-        #                plus latest and earliest Python versions
-        #                on all supported OSes
-        # - Compact (C): Second-latest and earliest supported Python versions
-        #                on all supported OSes, plus latest on Ubuntu
-        # - Extra   (X): Second-latest supported Python version on Ubuntu only
-        #
-        # | Python | Ubuntu  | Windows | macOS |
-        # |--------|---------|---------|-------|
-        # | 3.14   | O+C     | O       | O     |
-        # | 3.13   | O+C+X   | O+C     | O+C   |
-        # | 3.12   | O       |         |       |
-        # | 3.11   | O       |         |       |
-        # | 3.10   | O       |         |       |
-        # | 3.9    | O+C     | O+C     | O+C   |
-        #
-        # We should also consider to reduce the number of dependencies
-        # to avoid conflicts between them.
-        # See: https://github.com/PyThaiNLP/pythainlp/issues/935
+        # To optimize CI/CD resource utilization and manage dependency overhead,
+        # tests are categorized into four tiers based on their resource requirements
+        # and dependency complexity: "core", "compact", "extra", and "noauto".
+        # Test cases in "noauto" will not be included here.
+        # See details of test matrix in:
+        # https://github.com/PyThaiNLP/pythainlp/blob/dev/tests/README.md
         os: ["ubuntu-latest", "windows-latest", "macos-latest"]
         python-version: ["3.14", "3.9"] # Latest and earliest
         include: