Refresh datasheet and architecture diagrams to Workstation/Server structure

- build_nexus_one_ai_datasheet.py (root, outside cgit): new Product
  Structure section, Server S/M/L/Max tier table (was Starter/Basic/Pro/
  Max), Platform Roadmap section (7 capabilities). Regenerated docx + pdf.
- architecture-overview.svg / technical-service-flow.svg: relabeled tier
  banner to Server S/M/L/Max, fixed stale terminology (Agent builder ->
  Agent Studio, Connector sync -> MCP & Enterprise Connector sync, Pro/Max
  -> Server L/Max), added a one-line Workstation callout in existing
  whitespace. Verified by rendering both to PNG before committing.
- docs/README.md: notes docx/pdf/SVGs are current; the 3 jpg visuals still
  need a design refresh (raster images, tracked as follow-up).

docs/README.md

@@ -27,10 +27,15 @@ 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.
+full structure and the seven planned enterprise capabilities.
+
+`Nexus_One_AI_Datasheet.docx`/`.pdf`, `architecture-overview.svg`, and
+`technical-service-flow.svg` are updated to this structure — Server S/M/L/Max
+labeling throughout, a Workstation callout, and a Platform Roadmap section in
+the datasheet. The three `.jpg` visuals below (package overview, opportunity,
+tier comparison) are raster images from an earlier design pass and still
+predate this relabeling — they need a design refresh, not a text edit, and
+are tracked as follow-up work.
 
 ## Suggested Usage