fix(n8n): address review feedback and pass the verification scanner

- Telemetry: replace client-side PostHog (which read process.env, banned in
  verified nodes) with first-party `source: "N8N"` attribution on API requests,
  mirroring OpenClaw. Removes the undisclosed-collection concern entirely.
- Verification-scanner fixes: add credential icon, use NodeConnectionTypes.Main
  instead of the 'main' literal, wrap error paths in NodeApiError, stop shipping
  .d.ts / tsbuildinfo, and align the local eslint config with the scanner.
- Add offline unit tests (jest): entity-id guard, JSON-parse errors, poll-timeout
  loop, source attribution, and Return All pagination.
- Get Many: add a Return All option that pages through all memories.
- Docs: README telemetry note and an AGENTS.md Key Directories row.

Verified: build + tsc + eslint + 5 unit tests + live E2E against api.mem0.ai, and
the packed tarball passes @n8n/scan-community-package with zero violations.

integrations/n8n-nodes-mem0/.eslintrc.js

@@ -26,6 +26,14 @@ module.exports = {
 			files: ['./nodes/**/*.ts'],
 			plugins: ['eslint-plugin-n8n-nodes-base'],
 			extends: ['plugin:n8n-nodes-base/nodes'],
+			rules: {
+				// Superseded by the verification scanner's `@n8n/community-nodes`
+				// node-connection-type-literal rule, which requires
+				// NodeConnectionTypes.Main instead of the 'main' string literal.
+				// n8n's own scanner disables these two, so we match it.
+				'n8n-nodes-base/node-class-description-inputs-wrong-regular-node': 'off',
+				'n8n-nodes-base/node-class-description-outputs-wrong': 'off',
+			},
 		},
 	],
 };