Refactor Nexus One AI product structure and roadmap

- Add Workstation as an additive standalone category, kept out of
  TIER_ORDER so it never enters the Server S/M/L/Max upgrade ladder
- Add Server S/M/L/Max commercial labels for existing starter/basic/pro/max
  tiers (slugs, license format, and APIs unchanged)
- Rename portal UI terminology: Connectors -> MCP & Enterprise Connectors,
  Audit Log -> Governance & Audit, Model Manager -> Model Catalog,
  Agent Builder -> Agent Studio, Workflow Automation -> Workflow Designer,
  Multimodal Chat -> AI Workspace
- Fix branding.js workflow.html tier-gating bug and entry.yml missing tier var
- Document 7-capability platform roadmap and Workstation/Server structure
  in README.md and docs/README.md
- Ignore __pycache__/*.pyc build artifacts

docs/README.md

@@ -21,6 +21,17 @@ technical handoff point.
 | `nexus-one-ai-opportunity.jpg` | Business/problem framing visual. |
 | `nexus-one-ai-tier-comparison.jpg` | Tier and hardware comparison visual. |
 
+## Product Structure Note
+
+Nexus One AI, Powered by Cezen, now has two product categories: **Nexus One
+AI Workstation** (personal AI appliance) and **Nexus One AI Server** (Server
+S/M/L/Max — the same four tiers as before, relabeled). See the main repo
+`README.md` → "Product Structure" and "Platform Roadmap" sections for the
+full structure and the seven planned enterprise capabilities. The datasheet
+and tier-comparison visual below predate this relabeling and should be
+refreshed in a follow-up design pass — this is a text/terminology update,
+not a visual/collateral redesign.
+
 ## Suggested Usage
 
 - Start with the main repo `README.md` for installation and deployment paths.