Document Audita v2 operator migration and examples

docs/operations.md

@@ -124,10 +124,11 @@ membership, S3 object identity, or missing/tampered copies rerun prepare and
 its fixed descendants without requiring `--force`. Changing prepare selection
 semantics likewise reruns all fixed descendants; changing
 WhisperX language/service identity reuses prepare; changing a Seriatim merge
-transformation reuses prepare and transcribe; and changing an Audita model
-reuses prepare, transcribe, and merge while rebuilding transcript refinement.
-A trim change invalidates both render and extract through the fixed dependency
-relation, while a render-only change preserves the extract sibling.
+transformation reuses prepare and transcribe; and changing a selected Audita
+overlay, profile, or module sequence reuses prepare, transcribe, and merge while
+rebuilding transcript refinement. A trim change invalidates both render and
+extract through the fixed dependency relation, while a render-only change
+preserves the extract sibling.
 
 Operational timeouts, retry/concurrency tuning, executable paths,
 workspace/cache/spool placement, reports, diagnostics, and secret values are
@@ -409,6 +410,58 @@ execute. Deleting Narratio's local reference snapshots does not invalidate a
 complete durable extraction; missing snapshots are reconstructed only when a
 later extraction actually runs.
 
+## Migrating Audita and Provider Credentials
+
+This is a breaking clean cutover to Audita v2. Narratio does not translate an
+Audita v1 configuration, retain old field aliases, or generate a downstream
+configuration. Update both the deployed Audita executable/configuration and
+the Narratio pipeline before running polish. Retired Narratio fields are
+rejected by strict configuration loading; account for this break when choosing
+a release version.
+
+| Previous Narratio setting | New ownership and selection |
+| --- | --- |
+| `audita.base_url` | Audita v2 `backends.<id>.endpoint` |
+| `audita.total_llm_concurrency`, `proposal_llm_concurrency`, `validation_llm_concurrency` | Audita v2 `backends.<id>.concurrency` and optional `queue_capacity`; backend capacity is shared across roles |
+| `audita.model`, `validation_model` | Audita PromptKit profile files; optionally select them from Narratio with `audita.proposal_profile` and `validation_profile` |
+| `audita.llm_api_key` | `audita.credentials: [PROVIDER_KEY_NAME]`, matching each Audita backend's `credential` name |
+| `notarius.llm_api_key` | `notarius.credentials: [PROVIDER_KEY_NAME]`, matching references in Notarius-owned profiles |
+| `audita.work_dir_retention`, `report` | Remove; Audita's external configuration owns diagnostics and reporting |
+
+An Audita configuration can also be selected through `audita.config_path`,
+and `audita.overlay` selects an Audita overlay independently of Narratio's
+`--overlay`. Narratio forwards no implicit provider key: a single provider-named
+secret source may be listed for both adapters, and an Audita-only backend key
+may be listed only for Audita. Audita resolves credentials for all configured
+backends, including those not currently selected. Notarius looks up its own
+profiles; Narratio does not discover their credential names. Credential lists
+may be cleared with `[]` in a Narratio overlay.
+
+Prepare the external file from Audita's maintained
+[local example](https://gitea.maximumdirect.net/eric/audita/src/tag/v2.0.0/examples/minimal-config.yml),
+[service example](https://gitea.maximumdirect.net/eric/audita/src/tag/v2.0.0/examples/production-config.yml),
+and [v2 migration guide](https://gitea.maximumdirect.net/eric/audita/src/tag/v2.0.0/docs/migrations/v2.md).
+Before switching the executable, validate the file offline:
+
+```bash
+audita config validate --config /usr/local/etc/audita/config.yml
+```
+
+Use `audita config print-effective --config /usr/local/etc/audita/config.yml --view profiles`
+to inspect downstream profile selection without contacting a provider. For a
+production Audita configuration, leave ordinary reports enabled
+and debug disabled unless an operator deliberately chooses otherwise; Narratio
+does not override those settings. Audita writes `errors.yml`, `recoveries.yml`,
+and `report.md` beside the polished output when reporting is enabled. An
+exit-zero run with a valid transcript succeeds even if those reports describe
+recoverable errors or no applied corrections. See the [Audita integration
+contract](./integrations/audita.md) for report placement and limits.
+
+Narratio's polish resume evidence tracks selected config path, Audita overlay,
+profiles, ordered modules, description, schema, and output identity. Editing
+Audita-owned files behind unchanged selectors is invisible to Narratio; force
+polish with `narratio run-stage polish <session-id> --force` after such edits.
+
 ## External Command Lifecycle
 
 When an external command is cancelled or times out, Narratio terminates its
@@ -699,9 +752,10 @@ files. Existing environment variables—including empty values—always win.
 S3 `access_key_id` and `secret_access_key` are an optional pair of typed
 environment references. When both are absent, the AWS SDK retains its default
 credential provider chain. When both are configured, Narratio supplies their
-load-time resolved values through an explicit static provider. Audita's optional
-`llm_api_key` is likewise captured at pipeline load and supplied only through
-the child process's `AUDITA_LLM_API_KEY` override.
+load-time resolved values through an explicit static provider. Audita and
+Notarius credential lists likewise resolve at pipeline load. Each adapter
+receives only its listed names and captured values, with no alias mapping or
+ambient environment inheritance. See [configuration](./config.md#audita-selection-and-credentials).
 
 External adapter results are individually bounded before Narratio validates or
 materializes them. These per-file limits do not reserve disk space: prevent hard