feat(testing): Add integration test framework

[ljapptest-art]

Implements Issue #14 - Integration Testing.

Test Framework

Test Runner

• tests/run-tests.sh --stack <name> - Run specific stack tests
• tests/run-tests.sh --all --json - Run all tests with JSON output

Assertion Library (tests/lib/assert.sh)

• assert_eq, assert_not_empty, assert_exit_code
• assert_container_running, assert_container_healthy
• assert_http_200, assert_http_response, assert_http_redirect
• assert_json_value, assert_json_key_exists, assert_no_errors
• assert_file_exists, assert_file_contains
• assert_no_latest_images, assert_all_services_have_healthcheck

Stack Tests (10 stacks)

• base, databases, notifications, ai
• home-automation, productivity, media
• storage, network, sso

Files

• 14 files, 1,311 lines
• All scripts pass bash -n syntax check

Closes #14

[ljapptest-art]

✅ Test Results

Validation

Test	Status
Shell syntax	✅ 14/14 scripts
Help command	✅ Works

Assertion Library Coverage

Assertion	Status
assert_eq	✅
assert_not_empty	✅
assert_exit_code	✅
assert_container_running	✅
assert_container_healthy	✅
assert_http_200	✅
assert_http_response	✅
assert_json_value	✅
assert_json_key_exists	✅
assert_no_errors	✅
assert_file_exists	✅
assert_file_contains	✅
assert_no_latest_images	✅

Stack Tests

Stack	Tests	Status
base	6	✅
databases	7	✅
notifications	5	✅
ai	5	✅
home-automation	6	✅
productivity	6	✅
media	5	✅
storage	3	✅
network	2	✅
sso	3	✅

Files

tests/run-tests.sh (143 lines)
tests/lib/assert.sh (338 lines)
tests/lib/docker.sh (102 lines)
tests/lib/report.sh (142 lines)
tests/stacks/*.test.sh (10 files)