Plan Seriatim input implementation

docs/roadmap/5-seriatim-input-module.md

@@ -23,8 +23,7 @@ In scope:
 - input adapter registry wiring;
 - module metadata/capabilities for pipeline validation;
 - fixtures and tests;
-- config path to use the input module through a named pipeline profile if
-  config loading exists.
+- config compatibility through named pipeline profiles.
 
 Out of scope:
 
@@ -33,13 +32,16 @@ Out of scope:
 - transcript-specific behavior in runner/core packages;
 - support for every possible Seriatim schema variant.
 
-## Proposed Stages
+## Target End State
 
-### Seriatim Source Model
+The repository should contain a real Seriatim input-stage module that translates
+Seriatim minimal transcript JSON into the generic source model.
 
-Define module-local structs for the Seriatim minimal output schema.
+The Seriatim module should be registered under the stable input adapter key
+`seriatim`. It should be selectable through the existing input adapter registry
+and through pipeline-profile resolution when a profile binds `input: seriatim`.
 
-Expected external shape:
+The module should accept the Seriatim minimal output shape:
 
 - top-level `metadata`;
 - top-level `segments`;
@@ -49,57 +51,36 @@ Expected external shape:
 - segment `speaker`;
 - segment `text`.
 
-Keep these structs in the Seriatim input module package.
-
-### Parse And Validate
-
-Implement parser and validation behavior.
-
-Validation should cover:
-
-- valid JSON;
-- required metadata fields;
-- required segment fields;
-- unique segment IDs;
-- non-empty segment text;
-- valid start/end values as appropriate.
-
-Prefer clear module-specific errors.
-
-### Map To SourceDocument
-
-Map Seriatim data into the generic source model:
+The module should map Seriatim data into generic source values:
 
 - segment `id` becomes `SourceUnit.ID`;
 - segment `text` becomes `SourceUnit.Text`;
-- unit kind should identify transcript-like units without requiring core
-  packages to know transcript semantics;
-- `speaker`, `start`, and `end` become unit metadata;
-- Seriatim metadata becomes document metadata.
+- the document and unit kind strings identify transcript-like source material
+  without adding transcript-specific fields or types to core packages;
+- `speaker`, `start`, and `end` become source-unit metadata;
+- top-level Seriatim metadata becomes source-document metadata;
+- the resulting source document passes core source validation.
 
-The resulting `SourceDocument` should pass core source validation.
+The module should reject invalid Seriatim input with clear module-specific
+errors. Validation should cover:
 
-### Registry And CLI Wiring
+- valid JSON;
+- required top-level metadata and segments;
+- required segment fields;
+- unique segment IDs;
+- non-empty segment text;
+- valid start and end values.
 
-Register the module under a stable input adapter key, likely `seriatim`.
+The module should declare flat capabilities for pipeline validation. Initial
+capabilities should describe transcript-oriented source properties preserved by
+the adapter, including speaker and timestamp metadata.
 
-Declare module metadata for pipeline validation. Initial provided capabilities
-should include transcript-oriented metadata such as `speaker` and `timestamps`
-if those fields are preserved from Seriatim input.
+Implementation staging belongs in
+[`implementation.md`](implementation.md).
 
-If config and CLI support exist, add a minimal pipeline-profile fixture or test
-config using the Seriatim input module:
+## Fixtures And Tests
 
-```sh
-notarius run dnd-session --input ./transcript.json --only spells
-```
-
-The command may still use fake extract, merge, normalize, and output modules
-until checkpoint 6.
-
-### Fixtures And Tests
-
-Add fixtures and tests for:
+The checkpoint should add synthetic fixtures and focused tests for:
 
 - valid Seriatim minimal transcript;
 - malformed JSON;