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/bun/model-fetcher.ts

@@ -0,0 +1,107 @@
+/**
+ * Model fetcher — retrieves available models from each provider's API.
+ *
+ * Each function returns a sorted list of model IDs.
+ * Network errors return empty arrays (non-fatal).
+ */
+
+export interface ModelInfo {
+  id: string;
+  name: string;
+  provider: string;
+}
+
+const TIMEOUT = 8000;
+
+export async function fetchClaudeModels(): Promise<ModelInfo[]> {
+  const apiKey = process.env.ANTHROPIC_API_KEY;
+  if (!apiKey) return [];
+  try {
+    const res = await fetch('https://api.anthropic.com/v1/models', {
+      headers: {
+        'x-api-key': apiKey,
+        'anthropic-version': '2023-06-01',
+      },
+      signal: AbortSignal.timeout(TIMEOUT),
+    });
+    if (!res.ok) return [];
+    const data = await res.json() as { data?: Array<{ id: string; display_name?: string }> };
+    return (data.data ?? [])
+      .map(m => ({ id: m.id, name: m.display_name ?? m.id, provider: 'claude' }))
+      .sort((a, b) => a.id.localeCompare(b.id));
+  } catch {
+    return [];
+  }
+}
+
+export async function fetchCodexModels(): Promise<ModelInfo[]> {
+  const apiKey = process.env.OPENAI_API_KEY;
+  if (!apiKey) return [];
+  try {
+    const res = await fetch('https://api.openai.com/v1/models', {
+      headers: { 'Authorization': `Bearer ${apiKey}` },
+      signal: AbortSignal.timeout(TIMEOUT),
+    });
+    if (!res.ok) return [];
+    const data = await res.json() as { data?: Array<{ id: string }> };
+    return (data.data ?? [])
+      .map(m => ({ id: m.id, name: m.id, provider: 'codex' }))
+      .sort((a, b) => a.id.localeCompare(b.id));
+  } catch {
+    return [];
+  }
+}
+
+export async function fetchOllamaModels(): Promise<ModelInfo[]> {
+  try {
+    const res = await fetch('http://localhost:11434/api/tags', {
+      signal: AbortSignal.timeout(TIMEOUT),
+    });
+    if (!res.ok) return [];
+    const data = await res.json() as { models?: Array<{ name: string; model?: string }> };
+    return (data.models ?? [])
+      .map(m => ({ id: m.name, name: m.name, provider: 'ollama' }))
+      .sort((a, b) => a.id.localeCompare(b.id));
+  } catch {
+    return [];
+  }
+}
+
+export async function fetchGeminiModels(): Promise<ModelInfo[]> {
+  const apiKey = process.env.GEMINI_API_KEY;
+  if (!apiKey) return [];
+  try {
+    const res = await fetch(
+      `https://generativelanguage.googleapis.com/v1beta/models?key=${apiKey}`,
+      { signal: AbortSignal.timeout(TIMEOUT) },
+    );
+    if (!res.ok) return [];
+    const data = await res.json() as {
+      models?: Array<{ name: string; displayName?: string }>;
+    };
+    return (data.models ?? [])
+      .map(m => ({
+        id: m.name.replace('models/', ''),
+        name: m.displayName ?? m.name,
+        provider: 'gemini',
+      }))
+      .sort((a, b) => a.id.localeCompare(b.id));
+  } catch {
+    return [];
+  }
+}
+
+/**
+ * Fetch models for a specific provider.
+ */
+export async function fetchModelsForProvider(
+  provider: string,
+): Promise<ModelInfo[]> {
+  switch (provider) {
+    case 'claude': return fetchClaudeModels();
+    case 'codex': return fetchCodexModels();
+    case 'ollama': return fetchOllamaModels();
+    case 'gemini': return fetchGeminiModels();
+    default: return [];
+  }
+}