docs: add install/update instructions for effect-ts-guide skill

[konard]

Summary

Fixes #4

• Add README.md with canonical install command (--repo ProverCoderAI/effect-ts-skills --path skills/effect-ts-guide), a safe update/reinstall flow (rm -rf + re-install), and development setup instructions.
• Add installPaths array to .codex-plugin/plugin.json listing skills/effect-ts-guide explicitly, so tooling can discover the skill path without scanning the directory tree.

What this addresses from the issue

Issue scenario	Resolution
Root URL install fails with "Missing --path"	README documents the exact --path skills/effect-ts-guide flag
Reinstall fails on existing directory	README documents safe update flow: remove old copy, then re-install
No canonical install command published	README contains copy-pasteable install and update commands
No repo-level manifest for skill discovery	plugin.json now includes installPaths array

Test plan

• pnpm run check passes locally (lint, tests, validate:distribution, check:skill)
• Verify README renders correctly on GitHub
• Verify install command works end-to-end with skill-installer

🤖 Generated with Claude Code

[konard]

🤖 Solution Draft Log

This log file contains the complete execution trace of the AI solution draft process.

💰 Cost estimation:

• Public pricing estimate: $0.732996
• Calculated by Anthropic: $0.732996 USD
• Difference: $0.000000 (0.00%)

📊 Context and tokens usage:

Claude Opus 4.6:

• Context window: 36.6K / 1M input tokens (4%), 5.0K / 128K output tokens (4%)

Total: 26.0K + 695.2K cached input tokens, 5.0K output tokens, $0.634674 cost

Claude Haiku 4.5:

Total: 30.0K + 300.1K cached input tokens, 6.2K output tokens (10% of 64K output limit), $0.098323 cost

🤖 Models used:

• Tool: Anthropic Claude Code
• Requested: opus
• Main model: Claude Opus 4.6 (claude-opus-4-6)
• Additional models:
  • Claude Haiku 4.5 (claude-haiku-4-5-20251001)

📎 Log file uploaded as Gist (571KB)

• View complete solution draft log

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Now working session is ended, feel free to review and add any feedback on the solution draft.

[konard]

🔄 Auto-restart 1/3

Detected uncommitted changes from previous run. Starting new session to review and commit or discard them.

Uncommitted files:

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[konard]

🔄 Auto-restart 1/3 Log

This log file contains the complete execution trace of the AI solution draft process.

💰 Cost estimation:

• Public pricing estimate: $0.703307
• Calculated by Anthropic: $0.703307 USD
• Difference: $0.000000 (+0.00%)

📊 Context and tokens usage:

• Context window: 37.3K / 1M input tokens (4%), 4.8K / 128K output tokens (4%)

Total: 26.4K + 839.2K cached input tokens, 4.8K output tokens, $0.703307 cost

🤖 Models used:

• Tool: Anthropic Claude Code
• Requested: opus
• Model: Claude Opus 4.6 (claude-opus-4-6)

📎 Log file uploaded as Gist (988KB)

• View complete solution draft log

---

Now working session is ended, feel free to review and add any feedback on the solution draft.

[konard]

✅ Ready to merge

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• No CI/CD checks are configured for this repository
• No merge conflicts
• No pending changes

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