chore(release): cli 0.2.7 + docs + Mintlify auto-deploy workflow

Wraps up the AGENTRUSH CLI release across both clients.

Lint:
- Node Biome: collapse multi-line printError() in whoami.ts
- Python ruff: drop unused BRAND_COLOR import; replace EN DASH with
  HYPHEN-MINUS in app.py docstring

Release:
- Bump @mem0/cli and mem0-cli from 0.2.6 → 0.2.7 (patch)
- Add CHANGELOG.md (Keep a Changelog format) to both CLIs, seeded
  with the 0.2.7 entry covering whoami, agent-rush <add|search>, the
  PII safety prompt, and the new agent_rush.acknowledged_at config field

Docs:
- docs/platform/cli.mdx: new sections for `mem0 whoami` and
  `mem0 agent-rush <add|search>` with rule table, error-code hints,
  the launch copy-paste block, and the public-memory warning
- llms.txt coverage already in sync (no new .mdx files)

Mintlify auto-deploy:
- New .github/workflows/mintlify-deploy.yml — pings the deploy hook on
  every push to main, bypassing the GitHub App's path-detection bug
  that caused docs.mem0.ai drift (the recurring "trigger redeploy"
  commits). Workflow is a clean no-op until MINTLIFY_DEPLOY_HOOK_URL
  repo secret is configured in dashboard.

cli/node/src/commands/whoami.ts

@@ -10,9 +10,7 @@ export async function cmdWhoami(): Promise<void> {
 	const config = loadConfig();
 	const sessionId = config.platform?.defaultUserId;
 	if (!sessionId) {
-		printError(
-			"No default_user_id found. Run `mem0 init --agent` first.",
-		);
+		printError("No default_user_id found. Run `mem0 init --agent` first.");
 		process.exit(1);
 	}
 	console.log(`Your AGENTRUSH identifier:  ${colors.brand(sessionId)}`);