[LOGGING] Integrate Structured Logging Framework

[fentz26]

Problem

No structured logging framework:

• Using fmt.Printf or log.Println
• No log levels
• Not queryable
• No context propagation

Proposed Solution

zerolog Integration

import "github.com/rs/zerolog"

var log = zerolog.New(os.Stderr).With().Timestamp().Logger()

// Usage
log.Info().
    Str("task_id", task.ID).
    Str("status", task.Status).
    Dur("duration", elapsed).
    Msg("task completed")

// With context
ctx = log.With().Str("request_id", reqID).Logger().WithContext(ctx)
zerolog.Ctx(ctx).Info().Msg("processing request")

Log Levels

Level	Usage
Trace	Detailed debugging
Debug	Development info
Info	Normal operations
Warn	Potential issues
Error	Failures
Fatal	Unrecoverable

Acceptance Criteria

• zerolog or zap integrated
• Structured JSON output
• Log levels configurable
• Request ID propagation
• File and console output options
• Log rotation

References

• Parent Epic: 📊 Epic: Observability & Configuration #78