v0.20.6 rebuild platform environments from templates

scripts/export_antigravity_workspace.py

@@ -16,17 +16,20 @@ FILES = [
     "README.md",
     "docs/antigravity-clean-workspace.md",
     "docs/platform-adapters.md",
+    "docs/platform-branch-strategy.md",
     "scripts/dr.py",
     "scripts/deploy_adapters.py",
+    "scripts/update_platform_envs.py",
 ]
 
 DIRS = [
-    ".agent",
     "configs",
     "scripts/runtime",
     "scripts/reporting",
 ]
 
+ANTIGRAVITY_AGENT_SRC = REPO_ROOT / "platform_adapters" / "antigravity" / "agent"
+
 EMPTY_DIRS = [
     "projects",
 ]
@@ -80,6 +83,10 @@ def export_workspace(target: Path, *, force: bool, dry_run: bool) -> None:
             raise FileNotFoundError(src)
         copy_dir(src, target / rel, dry_run=dry_run)
 
+    if not ANTIGRAVITY_AGENT_SRC.exists():
+        raise FileNotFoundError(ANTIGRAVITY_AGENT_SRC)
+    copy_dir(ANTIGRAVITY_AGENT_SRC, target / ".agent", dry_run=dry_run)
+
     for rel in EMPTY_DIRS:
         if dry_run:
             print(f"dir  {rel} -> {target / rel}")