Add opt-in configuration overrides

docs/cli.md

@@ -306,6 +306,17 @@ runtime context or acquire configuration. It reports the intersection between
 declared scope capabilities and installed handlers, so an operation is listed
 only when the corresponding command is available.
 
+Scopes can opt in to transient overrides. For an opted-in scope, acquisition
+commands accept repeatable `--set POINTER=JSON`; comparison also accepts
+`--against-set POINTER=JSON` for the right side. Each assignment is passed to
+the loader in order, with `--set` or `--against-set` as its source label.
+The pointer and value are split at the first `=`, so pointer keys containing
+`=` cannot be addressed by these flags; JSON strings can contain `=`. Values
+use JSON types, including null, false, zero, and empty containers. ConfigKit
+owns override path validation and conflict handling. A selected scope must opt
+in before receiving overrides; for `--scope all`, every selected scope must
+support them.
+
 Applications can add `ckprompt.ConfigScope(loadEngine)` to the ConfigKit suite
 to expose PromptKit engine configuration through these handlers. The scope
 declares validate, show, sources, explain, and native diff. It does not install

docs/consumers/guide.md

@@ -255,6 +255,10 @@ owns operator syntax and report details. `Scope.Features` declares optional mode
 `View.Metadata` and `View.Findings` carry native path metadata and diagnostic
 records when available. `Findings.Messages` contains presentations associated
 with those records, while `Acquired.Diagnostics` carries independent messages.
+Set `Scope.Features.Overrides` only when the loader passes
+`Selection.Overrides` to ConfigKit as part of its normal load. The integration
+parses CLI records but cannot add them to an already-loaded result. The
+[CLI reference](../cli.md#configuration-scopes) describes the operator syntax.
 
 ## PromptKit configuration, definitions, and requirements
 

docs/roadmap/implementation.md

@@ -1,6 +1,6 @@
 # Shared reporting and PromptKit v0.20.0 implementation plan
 
-Status: implementation in progress; Stages 1–15 complete.
+Status: implementation in progress; Stages 1–16 complete.
 
 ## Scope, authority, and execution
 
@@ -571,6 +571,11 @@ model. Explicit-empty custom collections remain application-defined.
 
 ## Stage 16: Opt-in transient override acquisition
 
+**Complete.** Opted-in loaders receive ordered, independently copied native
+override records with safe flag labels. The root, ckconfig, and ckprompt
+workspace suites passed with Go 1.27.0, including scope preflight, comparison
+separation, native provenance, and load-error propagation.
+
 Add `Selection.Overrides []configkit.Override`. Preserve ordered records; nil
 means no CLI records. A loader opting in via `scope.Features.Overrides = true`
 reads those records during its ordinary load and supplies them to ConfigKit.