fix: redact smallest tts headers and report asr connection status

[harshitajain165]

Summary

Addresses both issues raised in #2203 (comment):

1. Security: SmallestTTSConfig.to_str(sensitive_handling=True) masked only params.api_key; headers (including a supported Authorization auth path merged into the actual HTTP request) were logged in plaintext during KEYPOINT vendor_config logging. Now redacted with the shared ten_ai_base.utils.redact_headers() helper, with test coverage for Authorization and API-key header variants.

2. Connection status: smallest_asr_python never called the base on_connected() after a successful WebSocket handshake, and never called on_disconnected() on connect failure or an unexpected socket close/error. The base class only emits CONNECTING before start_connection() runs, so the reported connection_status_changed state stayed "connecting" even once the socket was usable or had already failed. Now calls on_connected() immediately after ws_connect() succeeds, and on_disconnected() with the available error/close details before scheduling a reconnect.

Testing

Ran the real pytest suite (not just static checks) inside the project's Linux dev container, since ten_runtime_python is a compiled native extension:

• smallest_tts_python: 16/16 passed, including 3 new tests for header redaction.
• smallest_asr_python: 9/10 passed (new test_connection_status.py + all pre-existing tests). The one failure (test_invalid_params) is a pre-existing, unrelated environment issue — the dev container has a real SMALLEST_API_KEY set, which invalidates that specific test's "no key anywhere" assumption. Not touched by this diff (only start_connection() / _process_messages() were changed; test_invalid_params exercises on_init).

[ranchangxin-agora]

Please add the Guarder integration test results to this PR.
for the asr extension, run:

task asr-guarder-test EXTENSION=<asr_extension_name> CONFIG_DIR=tests/configs

for the tts extension, run:

task tts-guarder-test EXTENSION=<tts_extension_name> CONFIG_DIR=tests/configs

Please include the exact command, a summary of passed tests, and any failures.