feat(FN-3396): bundle Cursor CLI as a plugin provider with dashboard auth w

Merges FN-3396's full Cursor CLI provider integration (Steps 1–4): defines a CLI-backed provider contract, adds the `fusion-plugin-cursor-runtime` plugin package with process management and runtime probes, wires dashboard auth flows and UI (ProviderCard, onboarding modal, settings), and bundles the

Fusion-Task-Id: FN-3396

plugins/fusion-plugin-cursor-runtime/src/process-manager.ts

@@ -0,0 +1,46 @@
+import { runCursorCommand } from "./cli-spawn.js";
+
+function parseModelLines(raw: string): string[] {
+  return raw
+    .split(/\r?\n/)
+    .map((line) => line.trim())
+    .filter(Boolean)
+    .filter((line) => !line.toLowerCase().startsWith("usage"));
+}
+
+export async function discoverCursorModels(binary: string, timeoutMs = 5000): Promise<{ models: string[]; source: string; fallbackUsed: boolean; reason?: string }> {
+  const attempts: Array<{ args: string[]; source: string; structured: boolean }> = [
+    { args: ["models", "--json"], source: "models-json", structured: true },
+    { args: ["model", "list", "--json"], source: "model-list-json", structured: true },
+    { args: ["models"], source: "models-text", structured: false },
+  ];
+
+  for (const attempt of attempts) {
+    const res = await runCursorCommand(binary, attempt.args, timeoutMs);
+    if (res.code !== 0) continue;
+
+    const output = (res.stdout || "").trim();
+    if (!output) continue;
+
+    try {
+      const parsed = JSON.parse(output);
+      if (Array.isArray(parsed)) {
+        const ids = parsed
+          .map((entry) => (typeof entry === "string" ? entry : typeof entry?.id === "string" ? entry.id : undefined))
+          .filter((id): id is string => Boolean(id));
+        if (ids.length > 0) {
+          return { models: Array.from(new Set(ids)), source: attempt.source, fallbackUsed: !attempt.structured };
+        }
+      }
+    } catch {
+      // output is not JSON; continue with line-based fallback
+    }
+
+    const ids = Array.from(new Set(parseModelLines(output)));
+    if (ids.length > 0) {
+      return { models: ids, source: attempt.source, fallbackUsed: !attempt.structured };
+    }
+  }
+
+  return { models: [], source: "none", fallbackUsed: true, reason: "model discovery command unavailable" };
+}