Auto-detect S3 credentials and skip tests with clear reporting

- Tests automatically skip when S3 environment variables are missing
- Clear informative messages explain test execution (e.g. "Running 35/50 tests")
- Provides guidance on enabling S3 tests when credentials are absent
- Maintains backward compatibility with SKIP_S3_TESTS=1 override
- Enables agentic workflows to use `stack test` without environment exports

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: zyla

.claude/settings.local.json

@@ -10,7 +10,8 @@
       "Bash(stack build:*)",
       "Bash(mkdir:*)",
       "Bash(git rev-parse:*)",
-      "Bash(git remote get-url:*)"
+      "Bash(git remote get-url:*)",
+      "Bash(git rebase:*)"
     ],
     "deny": [],
     "ask": []

CLAUDE.md

@@ -23,14 +23,14 @@ stack build
 
 ### Running Tests
 ```bash
-# Run all tests (auto-detects S3 credentials and skips S3 tests if missing)
+# Run tests (auto-detects S3 credentials and skips S3 tests if missing)
 stack test
 
 # Run tests, skipping slow ones
 export SKIP_SLOW_TESTS=1
 stack test
 
-# Run tests, explicitly skipping S3 tests (recommended if no local S3/minio)
+# Explicitly skip S3 tests even if credentials are present
 export SKIP_S3_TESTS=1
 stack test
 
@@ -85,8 +85,8 @@ stack test --test-arguments --accept
 - The test suite includes integration tests that verify taskrunner behavior
 - **S3 Test Auto-Detection**: 15 tests require S3 credentials (marked with `# s3` directive in test files)
   - `stack test` automatically skips S3 tests if credentials are missing
-  - Set `SKIP_S3_TESTS=1` to explicitly skip S3 tests even if credentials are available
   - To run S3 tests, set: `TASKRUNNER_TEST_S3_ENDPOINT`, `TASKRUNNER_TEST_S3_ACCESS_KEY`, `TASKRUNNER_TEST_S3_SECRET_KEY`
+  - Use `SKIP_S3_TESTS=1` to explicitly skip S3 tests even when credentials are present
 - GitHub tests use a fake API server and don't require real GitHub credentials
 - The project uses Universum as an alternative Prelude
 - Build output and temporary files are in `.stack-work/`