perf: optimize MCP server (O(1) auth, compact JSON, trashedAt fix) + memento-note performance (lazy loading, server-side filtering, XSS fixes, dead code removal, security hardening)

MCP Server:
- Fix validateApiKey: O(1) direct lookup by shortId instead of loading all keys
- Add trashedAt:null filter to ALL note queries (trashed notes leaked in results)
- Compact JSON output (~40% smaller responses)
- Bounded session cache (Map with MAX_SESSIONS=500) to prevent memory leaks
- PostgreSQL connection pooling (connection_limit=10)
- Rewrite all 22 tool descriptions in clear English
- Fix /sse fallback to proper 307 redirect

memento-note Performance:
- loading=lazy on all note images
- Split notebooksRefreshKey from global refreshKey (note CRUD no longer re-fetches notebooks)
- Remove searchKey from trash count deps (no re-fetch on every keystroke)
- Server-side notebookId filter in getAllNotes() (biggest win)
- Skip collaborator fetch for non-shared notes (eliminates N+1 API calls)
- next/dynamic for MarkdownContent + 4 modals (code-split remark/rehype/KaTeX)
- Memoize DOMPurify sanitize with useMemo

Security:
- XSS: DOMPurify sanitize in note-card and note-history-modal
- Auth anti-enumeration: uniform errors in auth.ts
- CRON_SECRET mandatory on cron endpoints
- Rate limiting on login (5 attempts/min per email)
- Centralized API auth helpers (requireAuth/requireAdmin)
- randomize-labels changed GET→POST
- Removed debug endpoints (/api/debug/config, /api/debug/test-chat)

Cleanup:
- Removed dead code: .backup-keep, settings-backup, fix-*.js, debug-theme, fix-labels route
- Removed sensitive console.error in auth.ts
- Ollama fetchWithTimeout (30s/60s AbortController)
- i18n: full Arabic translation, Farsi missing keys
- Masonry drag-and-drop fix (localOrderMap, cross-section block)
- Sidebar notebook tooltip on truncation

memento-note/package-lock.json

@@ -55,6 +55,7 @@
         "date-fns": "^4.1.0",
         "diff": "^9.0.0",
         "dotenv": "^17.2.3",
+        "isomorphic-dompurify": "^3.12.0",
         "jsdom": "^29.0.2",
         "katex": "^0.16.27",
         "lucide-react": "^0.562.0",
@@ -8769,9 +8770,9 @@
       }
     },
     "node_modules/dompurify": {
-      "version": "3.4.0",
-      "resolved": "https://registry.npmjs.org/dompurify/-/dompurify-3.4.0.tgz",
-      "integrity": "sha512-nolgK9JcaUXMSmW+j1yaSvaEaoXYHwWyGJlkoCTghc97KgGDDSnpoU/PlEnw63Ah+TGKFOyY+X5LnxaWbCSfXg==",
+      "version": "3.4.2",
+      "resolved": "https://registry.npmjs.org/dompurify/-/dompurify-3.4.2.tgz",
+      "integrity": "sha512-lHeS9SA/IKeIFFyYciHBr2n0v1VMPlSj843HdLOwjb2OxNwdq9Xykxqhk+FE42MzAdHvInbAolSE4mhahPpjXA==",
       "license": "(MPL-2.0 OR Apache-2.0)",
       "optionalDependencies": {
         "@types/trusted-types": "^2.0.7"
@@ -9544,6 +9545,19 @@
       "integrity": "sha512-RHxMLp9lnKHGHRng9QFhRCMbYAcVpn69smSGcq3f36xjgVVWThj4qqLbTLlq7Ssj8B+fIQ1EuCEGI2lKsyQeIw==",
       "license": "ISC"
     },
+    "node_modules/isomorphic-dompurify": {
+      "version": "3.12.0",
+      "resolved": "https://registry.npmjs.org/isomorphic-dompurify/-/isomorphic-dompurify-3.12.0.tgz",
+      "integrity": "sha512-8n+j+6ypTHvriJwFOQ2qusQ6bzGjZVcR3jbe1pBpLcGI1dn4WIl0ctLBngqE5QttquQBAlKXwJeTMw+X7x7qKw==",
+      "license": "MIT",
+      "dependencies": {
+        "dompurify": "^3.4.2",
+        "jsdom": "^29.1.1"
+      },
+      "engines": {
+        "node": "^20.19.0 || ^22.13.0 || >=24.0.0"
+      }
+    },
     "node_modules/istanbul-lib-coverage": {
       "version": "3.2.2",
       "resolved": "https://registry.npmjs.org/istanbul-lib-coverage/-/istanbul-lib-coverage-3.2.2.tgz",
@@ -9641,27 +9655,27 @@
       "license": "MIT"
     },
     "node_modules/jsdom": {
-      "version": "29.0.2",
-      "resolved": "https://registry.npmjs.org/jsdom/-/jsdom-29.0.2.tgz",
-      "integrity": "sha512-9VnGEBosc/ZpwyOsJBCQ/3I5p7Q5ngOY14a9bf5btenAORmZfDse1ZEheMiWcJ3h81+Fv7HmJFdS0szo/waF2w==",
+      "version": "29.1.1",
+      "resolved": "https://registry.npmjs.org/jsdom/-/jsdom-29.1.1.tgz",
+      "integrity": "sha512-ECi4Fi2f7BdJtUKTflYRTiaMxIB0O6zfR1fX0GXpUrf6flp8QIYn1UT20YQqdSOfk2dfkCwS8LAFoJDEppNK5Q==",
       "license": "MIT",
       "dependencies": {
-        "@asamuzakjp/css-color": "^5.1.5",
-        "@asamuzakjp/dom-selector": "^7.0.6",
+        "@asamuzakjp/css-color": "^5.1.11",
+        "@asamuzakjp/dom-selector": "^7.1.1",
         "@bramus/specificity": "^2.4.2",
-        "@csstools/css-syntax-patches-for-csstree": "^1.1.1",
+        "@csstools/css-syntax-patches-for-csstree": "^1.1.3",
         "@exodus/bytes": "^1.15.0",
         "css-tree": "^3.2.1",
         "data-urls": "^7.0.0",
         "decimal.js": "^10.6.0",
         "html-encoding-sniffer": "^6.0.0",
         "is-potential-custom-element-name": "^1.0.1",
-        "lru-cache": "^11.2.7",
-        "parse5": "^8.0.0",
+        "lru-cache": "^11.3.5",
+        "parse5": "^8.0.1",
         "saxes": "^6.0.0",
         "symbol-tree": "^3.2.4",
         "tough-cookie": "^6.0.1",
-        "undici": "^7.24.5",
+        "undici": "^7.25.0",
         "w3c-xmlserializer": "^5.0.0",
         "webidl-conversions": "^8.0.1",
         "whatwg-mimetype": "^5.0.0",