security: fix critical auth gaps, SSRF, IDOR, and embedding error handling

CRITICAL:
- Add auth + admin check to 10 unprotected API routes (test-*, debug/*,
  config, models, fix-labels)
- Add CRON_SECRET bearer auth to /api/cron/reminders (was fully open)
- Add SSRF protection to getOllamaModels (blocks private/internal IPs)

HIGH:
- Fix getAllLabels() missing userId filter (leaked all users' labels)
- Fix /api/labels OR clause leaking other users' labels
- Fix IDOR in toggleAgent/getAgentActions (add ownership check)
- Fix getEmbeddings() returning [] on error in all 5 providers (corrupted
  semantic search with NaN cosine similarity) — now throws instead

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

memento-note/app/actions/ollama.ts

@@ -26,6 +26,24 @@ export async function getOllamaModels(baseUrl: string): Promise<{ success: boole
     // Ensure URL doesn't end with slash
     const cleanUrl = baseUrl.replace(/\/$/, '')
 
+    // SSRF protection: block internal/private IPs
+    try {
+        const parsed = new URL(cleanUrl)
+        const hostname = parsed.hostname.toLowerCase()
+        const blockedHosts = ['localhost', '127.0.0.1', '0.0.0.0', '::1', '169.254.169.254']
+        if (blockedHosts.includes(hostname)) {
+            return { success: false, models: [], error: 'Private/internal URLs are not allowed' }
+        }
+        if (hostname.startsWith('10.') || hostname.startsWith('172.') || hostname.startsWith('192.168.') || hostname.startsWith('fc') || hostname.startsWith('fd')) {
+            return { success: false, models: [], error: 'Private/internal URLs are not allowed' }
+        }
+        if (parsed.protocol !== 'http:' && parsed.protocol !== 'https:') {
+            return { success: false, models: [], error: 'Only http/https protocols allowed' }
+        }
+    } catch {
+        return { success: false, models: [], error: 'Invalid URL' }
+    }
+
     try {
         const response = await fetch(`${cleanUrl}/api/tags`, {
             method: 'GET',