fix(wiki): add silence topic for GJ 672 (Nova Estrada), fix M→G header

Founding agreement land allocation ambiguities — crisis waiting to happen.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

wiki/star-systems/GJ-672/index.md

@@ -1,5 +1,5 @@
 # Nova Estrada
-**GJ 672** | M-type | deep_frontier
+**GJ 672** | G-type | deep_frontier
 
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@@ -40,9 +40,13 @@ No institutional presence. Governance by community meeting — all adults partic
 
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+## Silence Topic
+
+The founding agreement's land allocation terms. The original twenty-eight families each received a parcel under terms specified in the founding agreement. The agreement was drafted in haste during the expedition's final transit and signed without the legal review that a more established community would have required. Several of the allocation terms are ambiguous about inheritance, subdivision, and what happens when new families — born or arrived — need land. The community is thirty years old and the ambiguities have not yet produced a crisis. They will. The founding families know which clauses are ambiguous and have not raised the issue publicly because raising it means admitting the founding document is flawed, and the founding document is the only institutional structure the community has.
+
 ## Narrative Hook
 
-A wave_5 settlement at hop 18, thirty years old and still building, named "new road" by founders who believed the deep corridor's development would carry them forward — a belief that has not yet been tested by the corridor's first real disruption.
+A wave_5 settlement at hop 18, thirty years old and still building, whose founding agreement was drafted in transit and signed without review — and whose ambiguous land allocation terms are a crisis that hasn't happened yet.
 
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