refactor(tooling): T-1293 — atlas map, and the generator that must not run

The star-map family was the last unported part of the tree, and it never had
a ticket. Two of its scripts become `reach atlas map` verbs, nested under
atlas like planet (D-243: the Reach map is the ladder's top rung):

- `reach atlas map data [--check]` regenerates client/data/star_map_data.json.
  The regenerated file differs by one line: `_meta.note`, which named the
  old script's path.
- `reach atlas map svg` renders the concentric SVG (+ PNG), byte-identical
  to the old script's output on the same data.

make check-star-map and star-map-data stay as one-line delegates, because
pre-pr-client and pre-pr-validate depend on check-star-map.

generate-star-map.py, its seed, sculpt-star-map.py and tune-star-map-topology.py
are archived, not ported. The generator rewrites docs/design/star-map.json
unconditionally from an S-NNN-keyed seed, so re-running it would erase the GJ
migration and every hand edit since; sculpt and tune only understand S-NNN
edges. .claude/rules/diagrams.md was telling agents to "edit the generator
and re-run it". It now distinguishes the live concentric render, the seven
frozen S-keyed sector .d2 files (T-1294), and the two SVGs that never had a
generator in the repo.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

client/data/star_map_data.json

@@ -3,7 +3,7 @@
     "generated_from": "star-map.json + systems.db + wiki/star-systems",
     "system_count": 301,
     "edge_count": 335,
-    "note": "Client-side star map + atlas orbital data. Regenerate with: tooling/generate-star-map-data.py"
+    "note": "Client-side star map + atlas orbital data. Regenerate with: reach atlas map data"
   },
   "nodes": [
     {