Document and validate Notarius extraction workflows

docs/troubleshooting.md

@@ -117,6 +117,118 @@ Safe fix:
 
 Relevant reference: [CLI artifact selection](./cli.md).
 
+## Notarius executable missing
+
+Symptom:
+
+- extraction fails while resolving or starting the Notarius executable.
+
+Likely causes:
+
+- `pipeline.notarius.binary` is not installed, executable, or on `PATH`;
+- a configured executable path is wrong.
+
+Safe fix:
+
+- install a compatible Notarius release or correct the binary setting, then
+  rerun extraction.
+
+Relevant references: [Notarius configuration](./config.md#notarius-output-entries)
+and [Notarius integration](./integrations/notarius.md).
+
+## Notarius exits nonzero
+
+Symptom:
+
+- extraction reports a Notarius exit error instead of a receipt.
+
+Diagnostics:
+
+- inspect `runs/{run_id}/extract/notarius.stderr.log`; stdout is reserved for
+  the receipt and is not merged with diagnostics.
+
+Safe fix:
+
+- correct the reported Notarius pipeline, input, provider, or configuration
+  failure and rerun extraction. Do not edit a staged output bundle into place.
+
+Relevant reference: [Operations: Extraction Workflow](./operations.md#extraction-workflow).
+
+## Notarius receipt or index incompatible
+
+Symptom:
+
+- extraction rejects the receipt schema, pipeline identity, bundle/index path,
+  lane descriptor, or payload path even though Notarius exited successfully.
+
+Likely causes:
+
+- Narratio and Notarius versions disagree on their consumer contract;
+- the configured pipeline or lane constraints are stale;
+- output paths escape the bundle or traverse symlinks.
+
+Safe fix:
+
+- compare installed Notarius output with the canonical Notarius contracts,
+  align `pipeline.notarius` constraints, and rerun. Do not bypass confinement or
+  schema checks.
+
+Relevant reference: [Notarius integration](./integrations/notarius.md).
+
+## Required Notarius lane rejected or missing
+
+Symptom:
+
+- extraction fails because a configured lane is rejected, missing, duplicated,
+  or incompatible, including after a zero exit.
+
+Safe fix:
+
+- inspect the Notarius diagnostic log and bundle rejection/warning information;
+- correct the Notarius module or the exact declared lane contract;
+- remove an output declaration only if downstream consumers genuinely no longer
+  require that source, then rerun extraction.
+
+Every configured output is required. Narratio does not promote a partial result.
+
+## Extraction resume invalidated
+
+Symptom:
+
+- a previously successful extraction runs again during ordinary continuation.
+
+Likely causes:
+
+- the executable/config path, pipeline ID, timeout, working directory, or
+  configured output contracts changed;
+- the durable bundle, index, lane set, provenance, regular-file status, or
+  checksum no longer validates.
+
+Safe fix:
+
+- allow the automatic rerun after verifying the current configuration. Treat
+  an unsafe path or symlink error as filesystem corruption or tampering and
+  investigate it rather than replacing files manually.
+
+## Notarius transitive configuration changed
+
+Symptom:
+
+- Notarius profiles, prompts, modules, imported files, or references changed,
+  but Narratio still considers the previous extraction resumable.
+
+Safe fix:
+
+```bash
+narratio run-stage extract 2026-04-04 --force
+```
+
+Narratio fingerprints its invocation contract, not the contents of transitive
+Notarius inputs. Always force extraction after changing them; downstream
+successful stages are then marked stale normally.
+
+Relevant reference: [Operations: Extraction Workflow](./operations.md#extraction-workflow).
+
 ## Previous-session artifact input missing
 
 Symptom: