This change updates the environment variables injected by the worker controller
to match the standard names expected by Temporal SDKs:

- TEMPORAL_HOST_PORT → TEMPORAL_ADDRESS
- TEMPORAL_TLS_KEY_PATH → TEMPORAL_TLS_CLIENT_KEY_PATH
- TEMPORAL_TLS_CERT_PATH → TEMPORAL_TLS_CLIENT_CERT_PATH
- Added TEMPORAL_TLS=true when mTLS is enabled

Also updates all tests, documentation, and demo code to use the new
environment variable names.

Fixes #128

Prefix the build ID environment variable with TEMPORAL_ to match
the naming convention of other Temporal SDK environment variables.

- Add unit test that verifies environment variables injected by the
  controller are compatible with go.temporal.io/sdk/contrib/envconfig
- Update demo client code to use envconfig.LoadDefaultClientOptions()
  instead of manually constructing client options
- Add go.temporal.io/sdk/contrib/envconfig dependency

This ensures that the environment variables we inject follow the
standard patterns expected by the Temporal SDK ecosystem.

- Rename TestNewDeploymentWithOwnerRef_EnvironmentVariables to
  TestNewDeploymentWithOwnerRef_EnvironmentVariablesAndVolumes to better
  reflect that it tests both env vars and volume mounts
- Add exhaustive coverage for all environment variables injected by
  the controller in TestNewDeploymentWithOwnerRef_EnvConfigSDKCompatibility
- Add verification that TLS is not configured for non-mTLS connections

Addresses:
- #130 (comment)
- #130 (comment)

Changed test HostPort from localhost:7233 to test.temporal.example:9999
to ensure we're testing actual environment variable parsing rather than
potentially getting default values from the envconfig package.

This makes the test more reliable for detecting configuration issues.

The demo module has its own go.mod file and also needs the
go.temporal.io/sdk/contrib/envconfig dependency for CI builds
to succeed when controller-gen scans all code paths.

- Include actual values in error messages for better debugging
- Generate self-signed certificates for TLS envconfig testing
- Enable full TLS test coverage with valid certificate files

Addresses:
- #130 (comment)
- #130 (comment)

- Remove expectedAddress and expectTLS fields from test cases
- Infer expected values directly from connection spec
- Simplifies test structure and reduces duplication

Addresses:
- #130 (comment)
- #130 (comment)

- Use pem.Encode() with os.Create() to write directly to files
- Replace pem.EncodeToMemory() + os.WriteFile() pattern
- Use t.TempDir() for proper test file cleanup
- Reduces memory allocation and improves performance
- Add proper file handle cleanup with defer statements

Addresses: #130 (comment)

- Remove assertions for certificate paths that were just set by t.Setenv()
- Keep only the meaningful assertion for TEMPORAL_TLS set by deployment
- Eliminates superfluous test code that doesn't add validation value

Addresses: #130 (comment)

Co-authored-by: Copilot <[email protected]>

- Reorganize imports to follow Go conventions (separate stdlib/external/internal)
- Consolidate TLS and non-TLS test logic into unified flow
- Add certificate path validation against expected volume mount paths
- Fix slice modification to properly override certificate paths with temp files
- Improve test structure by validating deployment env vars before overriding
- Remove redundant code duplication between TLS and non-TLS branches

Replace defer statements with t.Cleanup for file closure to follow
Go testing best practices. t.Cleanup is preferred in test functions
as it ensures cleanup runs even if the test panics or exits early.