Add PromptKit requirements command

docs/roadmap/implementation.md

@@ -1,6 +1,6 @@
 # Implement PromptKit requirements inspection
 
-Status: in progress; Stages 1 and 2 are complete.
+Status: in progress; Stages 1 through 3 are complete.
 
 ## Authority and working rules
 
@@ -239,6 +239,18 @@ suite factories or loaders. Normal flag conversion still applies on help;
 do not add a special bypass for malformed variable occurrences. Namespace
 collision/root-placement enforcement stays with the existing core installer.
 
+**Completed:** Added the optional `promptkit requirements show` command, typed
+bindings, per-invocation variable assignment parsing, format preflight, and
+buffered YAML delivery in `integrations/ckprompt/command.go`. Extended
+`command_test.go` for requirements-only and all-capability trees, help, request
+forwarding, selector/configuration presence, variable grammar, singleton
+overrides, repeated executions, and usage preflight. Focused optional-family and
+requirements command tests passed with `GOTOOLCHAIN=local go test
+./integrations/ckprompt -run
+'Test(CommandBuildsIndependentOptionalTrees|CatalogCommandTreesAreIndependentAndOmitShow|RequirementsCommandCapturesContextAndVariableAssignments|RequirementsCommandUsageFailuresPrecedeApplicationPreparation)$'
+-count=1`; `GOTOOLCHAIN=local go test ./...` from `integrations/ckprompt` also
+passed. No material limitations were encountered.
+
 ## Stage 4: Verify native semantics, lifecycle, and failure delivery
 
 **Outcome:** the installed command demonstrably delegates discovery to PromptKit