feat: eval CLI tools + docs cleanup

Add eval:list, eval:compare, eval:summary CLI scripts for exploring
eval history from ~/.gstack-dev/evals/. eval:compare reuses the shared
comparison functions from eval-store.ts.

- eval:list: sorted table with branch/tier/cost filters
- eval:compare: thin wrapper around compareEvalResults + formatComparison
- eval:summary: aggregate stats, flaky test detection, branch rankings
- Remove unused @anthropic-ai/claude-agent-sdk from devDependencies
- Update CLAUDE.md: streaming docs, eval CLI commands, remove Agent SDK refs
- Add GH Actions eval upload (P2) and web dashboard (P3) to TODOS.md

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

package.json

@@ -17,7 +17,10 @@
     "test:e2e": "EVALS=1 bun test test/skill-e2e.test.ts",
     "skill:check": "bun run scripts/skill-check.ts",
     "dev:skill": "bun run scripts/dev-skill.ts",
-    "start": "bun run browse/src/server.ts"
+    "start": "bun run browse/src/server.ts",
+    "eval:list": "bun run scripts/eval-list.ts",
+    "eval:compare": "bun run scripts/eval-compare.ts",
+    "eval:summary": "bun run scripts/eval-summary.ts"
   },
   "dependencies": {
     "playwright": "^1.58.2",
@@ -37,7 +40,6 @@
     "devtools"
   ],
   "devDependencies": {
-    "@anthropic-ai/claude-agent-sdk": "^0.2.75",
     "@anthropic-ai/sdk": "^0.78.0"
   }
 }