feat(wfe-server): gRPC reflection, auto-generated schema endpoints, Dockerfile

- tonic-reflection for gRPC service discovery
  - /schema/workflow.json (JSON Schema from schemars derives)
  - /schema/workflow.yaml (same schema in YAML)
  - /schema/workflow.proto (raw proto file)
  - Multi-stage alpine Dockerfile with all executor features
  - Comprehensive configuration reference (wfe-server/README.md)
  - Release script (scripts/release.sh)
  - Bumped to 1.8.1

wfe-deno/Cargo.toml

@@ -9,7 +9,7 @@ description = "Deno bindings for the WFE workflow engine"
 
 [dependencies]
 wfe-core = { workspace = true, features = ["test-support"] }
-wfe = { version = "1.8.0", path = "../wfe", registry = "sunbeam" }
+wfe = { version = "1.8.1", path = "../wfe", registry = "sunbeam" }
 deno_core = { workspace = true }
 deno_error = { workspace = true }
 tokio = { workspace = true }