Add/update multi node/multi GPU test scripts (#2410)

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## 📌 Description

- Renames the unit testing script to more accurately reflect current
usage
- adds multi-node and multi-GPU testing scripts
- refactors common code for those 3 scripts into a separate file

## 🔍 Related Issues

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## 🚀 Pull Request Checklist

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request, please make sure the following items are complete.

### ✅ Pre-commit Checks

- [x] I have installed `pre-commit` by running `pip install pre-commit`
(or used your preferred method).
- [x] I have installed the hooks with `pre-commit install`.
- [x] I have run the hooks manually with `pre-commit run --all-files`
and fixed any reported issues.

> If you are unsure about how to set up `pre-commit`, see [the
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## 🧪 Tests

- [ ] Tests have been added or updated as needed.
- [ ] All tests are passing (`unittest`, etc.).

## Reviewer Notes

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<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Chores**
* Centralized and consolidated test orchestration and utilities for
consistent unit, multi‑GPU, and multi‑node test runs.
* Improved environment handling, install/verify flows, and deterministic
test sampling across runners.
* **New Features**
* Added dry‑run mode, clearer test‑mode banners, and detailed execution
and dry‑run summaries for easier test planning and reporting.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: dierksen

scripts/task_run_unit_tests.sh

@@ -0,0 +1,94 @@
+#!/bin/bash
+
+set -eo pipefail
+
+# Get the directory where this script is located
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+# Source test environment setup (handles package overrides like TVM-FFI)
+source "${SCRIPT_DIR}/setup_test_env.sh"
+
+# Source common test functions
+# shellcheck disable=SC1091  # File exists, checked separately
+source "${SCRIPT_DIR}/test_utils.sh"
+
+# Find and filter test files based on pytest.ini exclusions
+find_test_files() {
+    echo "Reading pytest.ini for excluded directories..."
+    EXCLUDED_DIRS=""
+    if [ -f "./pytest.ini" ]; then
+        # Extract norecursedirs from pytest.ini and convert to array
+        NORECURSEDIRS=$(grep "^norecursedirs" ./pytest.ini | sed 's/norecursedirs\s*=\s*//' | sed 's/#.*//')
+        if [ -n "$NORECURSEDIRS" ]; then
+            EXCLUDED_DIRS=$(echo "$NORECURSEDIRS" | tr ',' ' ' | tr -s ' ')
+            echo "⚠️  WARNING: Excluding directories from pytest.ini: $EXCLUDED_DIRS"
+            echo ""
+        fi
+    fi
+
+    echo "Finding all test_*.py files in tests/ directory..."
+
+    # Find all test_*.py files
+    ALL_TEST_FILES=$(find tests/ -name "test_*.py" -type f | sort)
+
+    # Filter out excluded files based on directory exclusions
+    TEST_FILES=""
+    for test_file in $ALL_TEST_FILES; do
+        exclude_file=false
+        test_dir=$(dirname "$test_file")
+
+        for excluded_dir in $EXCLUDED_DIRS; do
+            excluded_dir=$(echo "$excluded_dir" | xargs)  # trim whitespace
+            if [ -n "$excluded_dir" ]; then
+                # Check if this file's directory should be excluded
+                if [[ "$test_dir" == *"/$excluded_dir" ]] || [[ "$test_dir" == "tests/$excluded_dir" ]] || [[ "$test_dir" == *"/$excluded_dir/"* ]]; then
+                    exclude_file=true
+                    break
+                fi
+            fi
+        done
+
+        if [ "$exclude_file" = false ]; then
+            TEST_FILES="$TEST_FILES $test_file"
+        fi
+    done
+
+    # Clean up whitespace
+    TEST_FILES=$(echo "$TEST_FILES" | xargs)
+
+    if [ -z "$TEST_FILES" ]; then
+        echo "No test files found in tests/ directory (after exclusions)"
+        exit 1
+    fi
+
+    echo "Found test files:"
+    for test_file in $TEST_FILES; do
+        echo "  $test_file"
+    done
+    echo ""
+}
+
+# Main execution
+main() {
+    # Parse command line arguments
+    parse_args "$@"
+
+    # Print test mode banner
+    print_test_mode_banner
+
+    # Install and verify (includes precompiled kernels)
+    install_and_verify
+
+    # Find test files (unique to unit tests - auto-discovery)
+    find_test_files
+
+    # Execute tests or dry run
+    if [ "$DRY_RUN" == "true" ]; then
+        execute_dry_run "$TEST_FILES"
+    else
+        execute_tests "$TEST_FILES"
+    fi
+
+    exit "$EXIT_CODE"
+}
+
+main "$@"