feat(electrobun): project wizard phases 1-5 (WIP)

- sanitize.ts: input sanitization (trim, control chars, path traversal)
- provider-scanner.ts: detect Claude/Codex/Ollama/Gemini availability
- model-fetcher.ts: live model lists from 4 provider APIs
- ModelConfigPanel.svelte: per-provider config (thinking, effort, sandbox, temperature)
- WizardStep1-3.svelte: split wizard into composable steps
- CustomDropdown/Checkbox/Radio: themed UI components
- provider-handlers.ts: provider.scan + provider.models RPC
- Wire providers into wizard step 3 (live detection + model lists)
- Replace native selects in 5 settings panels with CustomDropdown

ui-electrobun/src/shared/pty-rpc-schema.ts

@@ -236,6 +236,11 @@ export type PtyRPCRequests = {
     params: { url: string; target: string; branch?: string };
     response: { ok: boolean; error?: string };
   };
+  /** Probe a git remote URL (ls-remote). Returns branches on success. */
+  "git.probe": {
+    params: { url: string };
+    response: { ok: boolean; branches: string[]; defaultBranch: string; error?: string };
+  };
 
   // ── Project templates RPC ───────────────────────────────────────────────────
 
@@ -251,6 +256,39 @@ export type PtyRPCRequests = {
       }>;
     };
   };
+  /** Create a project from a template with real scaffold files. */
+  "project.createFromTemplate": {
+    params: { templateId: string; targetDir: string; projectName: string };
+    response: { ok: boolean; path: string; error?: string };
+  };
+
+  // ── Provider RPC ──────────────────────────────────────────────────────────
+
+  /** Scan for available AI providers on this machine. */
+  "provider.scan": {
+    params: Record<string, never>;
+    response: {
+      providers: Array<{
+        id: string;
+        available: boolean;
+        hasApiKey: boolean;
+        hasCli: boolean;
+        cliPath: string | null;
+        version: string | null;
+      }>;
+    };
+  };
+  /** Fetch model list for a specific provider. */
+  "provider.models": {
+    params: { provider: string };
+    response: {
+      models: Array<{
+        id: string;
+        name: string;
+        provider: string;
+      }>;
+    };
+  };
 
   // ── Window control RPC ─────────────────────────────────────────────────────