Add PromptKit definition inspection

docs/cli.md

@@ -225,6 +225,76 @@ environment-variable name; effective and historical secret fragments remain
 redacted. Empty location, inheritance, history, reason, and dependency lists are
 serialized as `[]`.
 
+## PromptKit definition inspection
+
+Applications can install prompt and profile inspection independently with
+`RegisterPromptKit`. Each installed handler constructs the selected engine once
+and asks PromptKit to inspect the named definition. Inspection reads the
+engine's captured configuration; it does not generate a prompt, contact a
+provider, or look up credentials.
+Prompt definitions and profile resolution remain owned by
+[PromptKit](https://pkg.go.dev/gitea.maximumdirect.net/eric/promptkit).
+
+```text
+example promptkit show prompt customer/summary --version 2 --format yaml
+example promptkit show prompt customer/summary
+example promptkit show profile customer-support --format yaml
+```
+
+Both commands require one ID operand and accept `--config`, `--overlay`, and
+`--format text|yaml` (default `text`). Prompt inspection also accepts singleton
+`--version`, defaulting to the empty string. PromptKit owns version selection:
+an omitted version works for a single-version ID, while an ambiguous ID is an
+operational error. These commands do not accept `--scope`; their namespace is
+`promptkit`.
+
+Prompt YAML has these fields. Input order is preserved and an empty input list is
+`[]`. The prompt hash is an opaque owning-library equality value.
+
+```yaml
+prompt_id: customer/summary
+prompt_version: "2"
+prompt_hash: opaque-value
+default_profile_id: customer-support
+inputs:
+  - name: topic
+    required: true
+    content_type: text/plain
+    description: Topic to summarize
+output_contract:
+  format: json
+  validation_mode: basic
+  schema_path: ""
+  repair_attempts: 2
+```
+
+Profile YAML preserves the effective values reported by PromptKit, including
+zero values and nested provider parameters. `api_key_env` is only an
+environment-variable name. `api_key_required` reports a direct credential
+requirement; neither field reports credential availability. A nil provider
+parameter map is displayed as `{}`.
+
+```yaml
+profile_id: customer-support
+effective_model_params:
+  backend_id: local
+  endpoint: https://example.invalid/v1
+  model: support-model
+  temperature: 0
+  max_tokens: 0
+  top_p: 0
+  timeout_seconds: 600
+  service_tier: ""
+  reasoning_effort: ""
+  api_key_env: ""
+  extra_params: {}
+api_key_required: true
+```
+
+Text uses labeled fields and includes nested `extra_params` values. A missing ID
+is a usage error. Blank, unknown, ambiguous, and canceled selections are
+operational inspection results from PromptKit and retain its error identity.
+
 ## Outcome status
 
 CommandKit usage failures use status `2`; operational failures use status `1`.