feat: agent builder, CWD support, auto-save, UI polish, unavailable tool handling

- Agent Builder: full CRUD with card grid, drag-and-drop model reorder, edit/delete
- Auto-save on edit with 600ms debounce, AbortController for concurrency, fieldset disabled until name entered
- Agent definitions stored as TOML with cwd field, loaded from global/project dirs
- Working directory: per-tab CWD override in Chat Settings, agent default CWD, auto-create on first message
- CWD validation: check-dir endpoint with ~ expansion, real-time validity indicator
- Subagent CWD validated against parent's effective CWD using path.relative
- Unavailable tool calls: caught gracefully, shown as tool call with error badge, model retries
- UI: tab bar border radius, sidebar border removed, chat input ghost style, scroll-to-bottom rectangle
- Skills dir collapse uses CSS rotation, Model Choice renamed to Chat Settings, System Prompt view removed
- Reusable SkillsBrowser/ToolPermissions with external mode for Agent Builder
- ModelSelector: Agent/Manual toggle, agent list, Agent Settings link
- Page router, skills recursive scanning, bin/up gopass removed, docker volume mounts

1 files changed, 6 insertions, 8 deletions

diff --git a/packages/core/src/tools/run-shell.ts b/packages/core/src/tools/run-shell.ts
index d549316..608c91d 100644
--- a/packages/core/src/tools/run-shell.ts
+++ b/packages/core/src/tools/run-shell.ts
@@ -11,12 +11,12 @@ export function createRunShellTool(workingDirectory: string): ToolDefinition {
 			"Execute a shell command in the working directory. Returns stdout, stderr, and exit code. Use for running tests, builds, git operations, package management, and other development tasks.",
 		parameters: z.object({
 			command: z.string().describe("The shell command to execute"),
-			timeout: z
-				.number()
-				.optional()
-				.describe("Timeout in milliseconds (default 2 minutes)"),
+			timeout: z.number().optional().describe("Timeout in milliseconds (default 2 minutes)"),
 		}),
-		execute: async (args: Record<string, unknown>, context?: ToolExecuteContext): Promise<string> => {
+		execute: async (
+			args: Record<string, unknown>,
+			context?: ToolExecuteContext,
+		): Promise<string> => {
 			const command = args.command as string;
 			const timeout = (args.timeout as number | undefined) ?? DEFAULT_TIMEOUT;
 
@@ -68,7 +68,5 @@ export function createRunShellTool(workingDirectory: string): ToolDefinition {
 }
 
 function getShell(): [string, string[]] {
-	return process.platform === "win32"
-		? ["powershell", ["-Command"]]
-		: ["bash", ["-c"]];
+	return process.platform === "win32" ? ["powershell", ["-Command"]] : ["bash", ["-c"]];
 }