Add capfox run wrapper command

[haskel]

Summary

• Implements capfox run wrapper command that checks server capacity before executing any command
• Works like time or nice - wrap any command with capfox run to check capacity first
• Supports all the same flags as capfox ask: --task, --complexity, --cpu, --mem, --gpu, --vram
• Updates version to 0.2.0

Features

• Exit codes:

  • 0-125: Command's exit code (passthrough)
  • 75: No capacity available (EX_TEMPFAIL from sysexits.h)
  • 126: Command not executable
  • 127: Command not found

• Fail-open behavior: If server is unreachable, command still executes

• Quiet mode: --quiet flag suppresses capfox output

• Reason display: --reason flag shows denial reasons

Usage

# Basic usage
capfox run ./script.sh

# With task name and complexity
capfox run --task ml_training --complexity 100 python train.py

# With resource estimates
capfox run --cpu 50 --mem 30 ./heavy.sh

# Quiet mode
capfox run --quiet ./script.sh

Test plan

• Unit tests for command structure and flags
• Tests for exit code handling
• Tests for task name derivation
• All existing tests pass