Add PromptKit catalog providers

docs/roadmap/implementation.md

@@ -1,6 +1,6 @@
 # Implement PromptKit comparison and catalogs
 
-Status: Stages 1–4 complete; remaining stages are planned.
+Status: Stages 1–5 complete; remaining stages are planned.
 
 ## Scope and authority
 
@@ -324,6 +324,22 @@ selection/input/state forwarding, load diagnostics/errors, and cancellation.
 Retain named-inspection tests. Custom empty catalogs and presentation belong to
 Stage 8; do not retest PromptKit's complete membership semantics.
 
+**Completion evidence (2026-10-12)**
+
+- Added the selected optional `ListPrompts` and `ListProfiles` callbacks to
+  `ckprompt.Suite` with the accepted signatures, and updated its declaration and
+  `FromEngine` documentation to cover catalogs alongside named inspection.
+- `FromEngine` now loads an engine only when a catalog callback is reached,
+  delegates to PromptKit's native `ListPrompts` and `ListProfiles`, and returns
+  the native ordered results with acquisition diagnostics.
+- Adapter tests compare both results with the same engine's public native
+  methods and cover context/selection/input/state forwarding, ConfigKit load
+  diagnostic and error identity retention, cancellation after loading, and a
+  nil-loader issue after all four callbacks are cleared. Existing named
+  inspection coverage remains in place.
+- `GOTOOLCHAIN=local go test -count=1 .` passed in `integrations/ckprompt`.
+  Family assembly and catalog presentation remain assigned to Stages 7 and 8.
+
 ## Stage 6: Implement the catalog YAML representation
 
 **Outcome:** small private helpers encode the explicitly selected CLI schema.