docs: extract guide design into reusable skills

skills/rules-case-study/SKILL.md

@@ -0,0 +1,18 @@
+---
+name: rules-case-study
+description: Use when explaining how a repository turns agent guidance into enforceable behavior across context files, skills, CLI checks, Git hooks, CI, worktrees, or PR review; build a concise, source-linked case-study page.
+---
+
+# Rules case study
+
+Show the control loop: context → skills → CLI → commit → review. The reader should see where a rule lives, what executes it, and how to verify it.
+
+## Workflow
+
+1. Inspect authoritative files before writing copy. Start with the repository context file, skill directory, command or database ledger, enforcement scripts, hooks, staged-file config, CI, and review policy. Use [the interview source map](references/interview-source-map.md) as a routing hint, then confirm paths in the target repository.
+2. Separate guidance from enforcement. A context file or skill teaches an agent; a CLI check, hook, CI job, or reviewer blocks or reports behavior. Never describe prose as mechanically enforced.
+3. For every example, show the rule, exact source path, enforcement point, verification command, and remaining gap. Prefer one concrete ratchet or hook example over a list of vague best practices.
+4. Add a skills shelf. Each skill needs a trigger, the lesson it carries, a tiny example, and a source link. Keep examples short enough to copy into an agent prompt.
+5. Include a read-only exploration prompt that asks an agent to map rules to evidence and gaps. Add copy feedback and bilingual labels if the host guide supports both languages.
+6. Use a dependency-free standalone page when the case study is mostly explanatory. Link back to the main guide and exact source files. Do not modify the source repository merely to document it.
+7. Verify dynamic stage and skill states, source links, copy behavior, language switching, no horizontal overflow, and the 390px/1920px/3840px viewports. The page is done when every claim has a source or is clearly labeled as a design recommendation.

skills/rules-case-study/evals/evals.json

@@ -0,0 +1,10 @@
+[
+  {
+    "prompt": "Explain a repository's AGENTS.md, reusable skills, UI ratchet script, Husky hooks, and PR review config as one teachable page.",
+    "expected_behavior": "Build a context → skills → CLI → commit → review pipeline; link every claim to an exact source path; distinguish guidance from enforcement; include a short read-only exploration prompt."
+  },
+  {
+    "prompt": "A skill says all pages need an h1 and a pre-commit script checks it. How should the case study describe that relationship?",
+    "expected_behavior": "Describe the skill/context as guidance and the script/hook as executable enforcement, then show the verification command and any gap between local hooks and CI."
+  }
+]

skills/rules-case-study/references/interview-source-map.md

@@ -0,0 +1,18 @@
+# Interview source map
+
+This map records the implementation inspected for the rules case study. Reconfirm paths when the source repository changes.
+
+| Concern | Source | Role |
+| --- | --- | --- |
+| Shared context | `AGENTS.md` | Stack, commands, product shape, conventions, and verification expectations. |
+| Reusable procedures | `.agents/skills/` | Focused workflows such as gates, frontend, Go API, repo DB, and skill writing. |
+| Machine-readable routing | `.agents/db/commands.json` | Canonical checks and code-generation commands. |
+| UI enforcement | `scripts/check-ui-contract.mjs` | Ratchet for buttons, catches, headings, colors, and duplicate components. |
+| Ratchet state | `scripts/ui-contract-baseline.json` | Baseline counts that new violations cannot exceed. |
+| Commit boundary | `.husky/pre-commit` | Runs lint-staged and the UI contract check. |
+| Commit message boundary | `.husky/commit-msg` | Runs commitlint. |
+| Staged-file tools | `.lintstagedrc.cjs` | Biome, ESLint, Prettier, and Buf formatting by file type. |
+| Independent review | `.pr-review.json` | Review focus, exclusions, security constraints, and test expectations. |
+| Agent roles | `.claude/agents/` | Prior-art scout, scoped implementer, and verifier responsibilities. |
+
+The source of truth is the repository. This table is a teaching map, not a replacement for reading the files.