Design system, rebrand styles, and lucide→Phosphor icon migration

.agents/index.md

@@ -2,6 +2,33 @@
 
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+## Core principles for every task
+
+Before writing code, walk this ladder. Stop at the first answer that works.
+
+1. **Does this need to exist?** → no: skip it (YAGNI)
+2. **Already in this codebase?** → reuse it, don't rewrite
+3. **Stdlib does it?** → use it
+4. **Native platform feature?** → use it
+5. **Installed dependency?** → use it
+6. **One line?** → one line
+7. **Only then:** the minimum that works
+
+Inspired by https://github.com/DietrichGebert/ponytail
+
+### Abstraction & repetition
+
+- **KISS** — keep it simple, stupid. Boring code beats clever code.
+- **WET > DRY** — write everything twice (or more) before abstracting. Three similar usages with diverging needs is the cue to extract; two is not.
+- Premature DRY couples unrelated code through a shared abstraction that ends up fighting both callers. Duplication is cheaper than the wrong abstraction.
+
+### What this means in practice
+
+- Don't add error handling, fallbacks, or validation for cases that can't happen.
+- Don't introduce helpers, wrappers, or config knobs "for later."
+- Don't refactor surrounding code while fixing a bug.
+- When tempted to abstract: count the call sites and check they actually want the same behavior. If not, leave the duplication.
+
 ## Essentials
 
 - Package manager: `pnpm`

package.json

@@ -41,6 +41,7 @@
     "@modelcontextprotocol/sdk": "^1.29.0",
     "@observablehq/plot": "^0.6.17",
     "@octokit/graphql": "^9.0.3",
+    "@phosphor-icons/react": "^2.1.10",
     "@radix-ui/react-dialog": "^1.1.15",
     "@radix-ui/react-dropdown-menu": "^2.1.16",
     "@radix-ui/react-toast": "^1.2.15",