feat: publish Gamertan Tend preview source

Sanitized root snapshot from private source commit a72903c63e1753f9e6ffbf40453c0830bdfc05c5 and tree 295641e67eef5979da76746d8ae271249568263e. Private development history and workflows are excluded by the exact allowlist.

AI-assisted: OpenAI Codex helped implement, test, and audit this preview.
Signed-off-by: Cole Speelman <crspeelman@gmail.com>

scripts/public-snapshot.allow

@@ -0,0 +1,44 @@
+.gitattributes
+.gitignore
+COPYRIGHT
+LICENSE
+README.md
+RELEASE.md
+SECURITY.md
+cmd/tend/main.go
+docs/ARCHITECTURE.md
+docs/DOGFOOD_EVIDENCE.md
+docs/PUBLIC_SNAPSHOT.md
+docs/THREAT_MODEL.md
+examples/LICENSE
+examples/README.md
+examples/blue-green/caddy-handler.template
+examples/blue-green/example-site@.service
+examples/blue-green/tend.json
+examples/singleton/tend.json
+go.mod
+internal/config/config.go
+internal/config/config_test.go
+internal/deploy/deploy.go
+internal/deploy/deploy_test.go
+internal/deploy/lock_linux.go
+internal/deploy/lock_other.go
+internal/deploy/operator.go
+internal/deploy/operator_test.go
+internal/deploy/ownership_linux.go
+internal/deploy/ownership_other.go
+internal/deploy/release.go
+internal/deploy/release_test.go
+internal/packager/packager.go
+internal/packager/packager_test.go
+internal/process/run.go
+internal/provenance/git.go
+internal/state/state.go
+internal/state/state_test.go
+internal/version/version.go
+release/tend.json
+scripts/check-licenses.sh
+scripts/export-public.sh
+scripts/public-snapshot.allow
+scripts/test-public-snapshot.sh
+scripts/verify.sh