OWNER: add canonical status model governance

Author: ToolboxAid

docs_build/dev/ProjectInstructions/addendums/status_model.md

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+# Status Model Governance
+
+## Canonical Statuses
+
+- `[ ]` Planned
+- `[.]` Wireframe
+- `[-]` Building
+- `[x]` Complete
+- `[!]` Blocked
+- `[D]` Deprecated
+
+## Overlay Rules
+
+- Planned = 70% black overlay
+- Wireframe = 80% black overlay
+- Building = 90% black overlay
+- Complete = 0% overlay / fully transparent
+- Blocked = yellow indicator
+- Deprecated = red indicator
+
+## Rule
+
+BACKLOG_MASTER.md is the source of truth for Build Path and Game Journey tile status.
+Manual tile status changes are prohibited.