fix: clear error logs and update Anthropic defaults

[icebear0828]

Summary

• add DELETE /admin/error-logs and wire the Errors dashboard clear action to remove current, rotated, and cursor files
• update Anthropic setup defaults to Opus 4.7 -> gpt-5.5 and Sonnet 4.6 -> gpt-5.4
• update the built-in Anthropic API-key catalog to Claude Opus 4.7

Tests

• npx vitest run tests/unit/routes/admin/error-logs.test.ts
• npm test
• npm run build
• git diff --check

[icebear0828]

建议小修后合：

• src/logs/error-log.ts:218-224 clearErrorLog() 每个 unlink 裸 try{}catch{} 吞掉，route 仍返回 {ok:true}，UI 显示已清空但实际可能没清。建议把成功标志冒泡上来。
• .github/workflows/release.yml 的 mac-x64 SMOKE_TIMEOUT=180 已被 fix: extend mac x64 packaged smoke timeout #560 squash 进 dev，这里 diff 会 no-op 合或者冲突。建议从本 PR 里删掉这段，scope 也更纯。
• PR title 是 "clear error logs and update Anthropic defaults" 但混了 mac-x64 timeout，建议要么拆要么改标题。