feat: add Claude usage tracking via CLI

Adds a Claude usage tracking feature that displays session, weekly, and Sonnet usage stats. Uses the Claude CLI's /usage command to fetch data (no API key required).

Features:
- Usage popover in board header showing session, weekly, and Sonnet limits
- Progress bars with color-coded status (green/orange/red)
- Auto-refresh with configurable interval
- Caching of usage data with stale indicator
- Settings section for refresh interval configuration

Server:
- ClaudeUsageService: Executes Claude CLI via PTY (expect) to fetch usage
- New /api/claude/usage endpoint

UI:
- ClaudeUsagePopover component with usage cards
- ClaudeUsageSection in settings for configuration
- Integration with app store for persistence

apps/server/src/routes/claude/index.ts

@@ -0,0 +1,44 @@
+import { Router, Request, Response } from "express";
+import { ClaudeUsageService } from "../../services/claude-usage-service.js";
+
+export function createClaudeRoutes(): Router {
+  const router = Router();
+  const service = new ClaudeUsageService();
+
+  // Get current usage (fetches from Claude CLI)
+  router.get("/usage", async (req: Request, res: Response) => {
+    try {
+      // Check if Claude CLI is available first
+      const isAvailable = await service.isAvailable();
+      if (!isAvailable) {
+        res.status(503).json({
+          error: "Claude CLI not found",
+          message: "Please install Claude Code CLI and run 'claude login' to authenticate"
+        });
+        return;
+      }
+
+      const usage = await service.fetchUsageData();
+      res.json(usage);
+    } catch (error) {
+      const message = error instanceof Error ? error.message : "Unknown error";
+
+      if (message.includes("Authentication required") || message.includes("token_expired")) {
+        res.status(401).json({
+          error: "Authentication required",
+          message: "Please run 'claude login' to authenticate"
+        });
+      } else if (message.includes("timed out")) {
+        res.status(504).json({
+          error: "Command timed out",
+          message: "The Claude CLI took too long to respond"
+        });
+      } else {
+        console.error("Error fetching usage:", error);
+        res.status(500).json({ error: message });
+      }
+    }
+  });
+
+  return router;
+}