- effective_timeout = min (mysql-wait_timeout, session-wait_timeout)

Signed-off-by: Wazir Ahmed <wazir@proxysql.com>

…mping

- Add range validation for client SET wait_timeout commands
- Implement clamping between 1 second (1000ms) and 20 days (1,728,000,000ms)
- Add warning messages when values are clamped due to ProxySQL limits
- Maintain MySQL compatibility by accepting larger values than global config
- Fix signed/unsigned comparison warning in wait_timeout assignment
- Ensures client applications don't break while enforcing safety limits

- Include wait_timeout value in session JSON output for monitoring/debugging
- Provides visibility into client-configured timeout values

- Add JSON parsing helper for PROXYSQL INTERNAL SESSION responses
- Add test_wait_timeout_json_values() function with 8 test cases:
  * Zero value (should clamp to 1 second)
  * Valid values (1s, 10s, 5min, 1hr, 24hr, 20 days)
  * Value exceeding 20 days (should clamp to maximum)
- Validate that wait_timeout appears in session JSON output
- Test plan increased from 4 to 12 tests total
- Provides comprehensive validation of wait_timeout clamping behavior

- Replace <json/json.h> include with <json.hpp> and proper nlohmann namespace
- Replace manual JSON parsing with fetch_internal_session() utility function
- Replace fail() calls with ok(false, ...) to follow TAP framework standards
- Add comprehensive JSON validation test for various wait_timeout values
- Include edge case testing: zero values, maximum values, and clamping behavior

Resolves compilation issues and enables proper testing of wait_timeout JSON output.

Key improvements:
- Fix timeout comparison in MySQL_Thread::idle_thread_to_kill_idle_sessions() to prevent underflow
- Use effective wait_timeout (minimum of global and session values) for idle timeout calculations
- Add proper newline characters to proxy_warning messages for consistent log formatting
- Increase test sleep times to account for global timeout enforcement
- Fix session timeout test durations to properly test timeout behavior

Technical changes:
- Replace broken min_idle calculation with proper effective wait_timeout logic
- Add std::min() usage to determine effective timeout from global and session values
- Ensure warning messages end with newline characters for proper log formatting
- Update test sleep durations to ensure proper timeout testing

Resolves potential timeout calculation bugs and ensures consistent timeout enforcement behavior.

Code improvements:
- Extract SESS_TO_SCAN_idle_thread constant to header file for better maintainability
- Replace magic number 128 with named constant in idle_thread_to_kill_idle_sessions()
- Improve code readability and consistency in session scanning logic

Test enhancements:
- Add mysql-poll_timeout configuration for more precise timeout testing
- Reduce test sleep times to 13 seconds for faster test execution
- Add diagnostic messages to clearly show timeout configurations in test output
- Ensure tests properly validate timeout enforcement with precise timing

The changes improve code maintainability and make tests more reliable and faster
while maintaining accurate timeout validation.

…ation

Enhance logging clarity:
- Replace generic IP address with detailed connection info including IP and port
- Use client_myds->addr.addr and client_myds->addr.port for precise identification
- Improve debuggability of timeout clamping and enforcement warnings

The warning messages now provide complete connection details, making it easier
to identify and troubleshoot timeout-related issues in ProxySQL logs.

The get_status_variable() function was only scanning worker threads
but ignoring auxiliary threads (idle threads) where timeout
terminations are detected. This caused the timeout termination
counter to show incorrect/zero values.

- Added idle thread scanning to both overloaded versions of
  get_status_variable() function
- Now properly collects metrics from both worker and idle threads
- Fixes the issue where proxysql_mysql_timeout_terminated_connections_total
  showed zero despite actual timeout terminations

Resolves the metrics reading issue identified in the previous commits.