Add fourth conflict layer: SSH ProxyCommand double tunneling causing
intermittent git push/pull failures when Shadowrocket TUN is active.
Structural improvements per skill best practices:
- Eliminate content duplication between SKILL.md and reference
- Rename proxy_fixes.md → proxy_conflict_reference.md for clarity
- Trim SKILL.md from 534 to 487 lines (under 500 limit)
- Shorten YAML description from 910 to 661 characters
- Fix "apply all four" listing 5 items (separate anti-pattern)
- Clarify Layer 4's relationship to Tailscale theme
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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