feat(web): add BackendRepoSelector component

gitnexus-web/src/components/BackendRepoSelector.tsx

@@ -0,0 +1,88 @@
+import { Server, ArrowRight } from 'lucide-react';
+import { BackendRepo } from '../services/backend';
+
+interface BackendRepoSelectorProps {
+  repos: BackendRepo[];
+  onSelectRepo: (repoName: string) => void;
+  backendUrl: string;
+  isConnected: boolean;
+}
+
+export const BackendRepoSelector = ({
+  repos,
+  onSelectRepo,
+  backendUrl,
+  isConnected,
+}: BackendRepoSelectorProps) => {
+  return (
+    <div className="p-8 bg-surface border border-border-default rounded-3xl">
+      {/* Icon */}
+      <div className="mx-auto w-20 h-20 mb-6 flex items-center justify-center bg-gradient-to-br from-accent to-node-interface rounded-2xl shadow-glow">
+        <Server className="w-10 h-10 text-white" />
+      </div>
+
+      {/* Title */}
+      <h2 className="text-xl font-semibold text-text-primary text-center mb-2">
+        Local Repositories
+      </h2>
+      <p className="text-sm text-text-secondary text-center mb-4">
+        Select an indexed repository from your local GitNexus server
+      </p>
+
+      {/* Connected status badge */}
+      {isConnected && (
+        <div className="flex items-center justify-center gap-2 mb-6">
+          <span className="w-2 h-2 bg-green-400 rounded-full animate-pulse" />
+          <span className="text-xs text-green-400">Connected to {backendUrl}</span>
+        </div>
+      )}
+
+      {/* Repo list or empty state */}
+      {repos.length > 0 ? (
+        <div className="max-h-80 overflow-y-auto space-y-2">
+          {repos.map((repo) => (
+            <button
+              key={repo.name}
+              onClick={() => onSelectRepo(repo.name)}
+              className="w-full p-4 bg-elevated border border-border-subtle rounded-xl hover:border-accent/50 hover:bg-hover transition-all text-left group"
+            >
+              <div className="flex items-center justify-between mb-2">
+                <span className="font-medium text-text-primary group-hover:text-accent transition-colors">
+                  {repo.name}
+                </span>
+                <ArrowRight className="w-4 h-4 text-text-muted group-hover:text-accent transition-colors" />
+              </div>
+              <div className="flex items-center gap-3 text-xs text-text-muted">
+                {repo.stats?.files != null && <span>{repo.stats.files} files</span>}
+                {repo.stats?.nodes != null && <span>{repo.stats.nodes} nodes</span>}
+                {repo.stats?.edges != null && <span>{repo.stats.edges} edges</span>}
+              </div>
+              <div className="text-xs text-text-muted mt-1">
+                Indexed {new Date(repo.indexedAt).toLocaleDateString()}
+              </div>
+            </button>
+          ))}
+        </div>
+      ) : (
+        <div className="text-center text-text-muted py-8">
+          <p className="text-sm mb-2">No indexed repositories found</p>
+          <p className="text-xs">
+            Run{' '}
+            <code className="px-1 py-0.5 bg-elevated rounded">gitnexus analyze</code>{' '}
+            in a repository
+          </p>
+        </div>
+      )}
+
+      {/* Bottom hints */}
+      <div className="mt-4 flex items-center justify-center gap-3 text-xs text-text-muted">
+        <span className="px-3 py-1.5 bg-elevated border border-border-subtle rounded-md">
+          {repos.length} {repos.length === 1 ? 'repo' : 'repos'}
+        </span>
+        <span className="px-3 py-1.5 bg-elevated border border-border-subtle rounded-md">
+          Pre-indexed
+        </span>
+      </div>
+    </div>
+  );
+};