feat: add is_subagent flag to agents, fix all lint/type/test issues

- Add is_subagent checkbox to agent editor; subagents are hidden from Chat Settings
- Add is_subagent field to AgentDefinition type, TOML serialization, and API route
- Filter subagents from ModelSelector agent list
- Fix all biome lint/format errors across codebase (useLiteralKeys, noNonNullAssertion, noExplicitAny, formatting, import sorting)
- Fix svelte-check errors (type narrowing in SkillsBrowser, ToolPermissions, SidebarPanel)
- Fix a11y warnings in App.svelte (label-control associations)
- Fix test mocks missing BackgroundShellStore, BackgroundTranscriptStore, createWebSearchTool, createYoutubeTranscribeTool
- Update stale 409 test to match current message-queuing behavior
- Exclude packaging/ and release/ dirs from biome to avoid linting stale build artifacts

1 files changed, 1 insertions, 1 deletions

diff --git a/bin/seed-opencode-keys.ts b/bin/seed-opencode-keys.ts
index c461592..c481b8d 100644
--- a/bin/seed-opencode-keys.ts
+++ b/bin/seed-opencode-keys.ts
@@ -2,7 +2,7 @@
 /**
  * Seed API keys from environment variables into the SQLite database.
  */
-import { setApiKey, getDatabasePath } from "../packages/core/src/index.js";
+import { getDatabasePath, setApiKey } from "../packages/core/src/index.js";
 
 console.log(`Database: ${getDatabasePath()}\n`);