Add campaign configuration support

docs/config.md

@@ -2,12 +2,13 @@
 
 ## 1. Overview
 
-Narratio loads two YAML files:
+Narratio loads three YAML files:
 
 - `pipeline.yml`: pipeline-level runtime configuration.
+- `campaign.yml`: stable campaign identity and campaign-level input defaults.
 - `session.yml`: per-session metadata and input selection.
 
-These commands load and validate both files before running:
+These commands load and validate all three files before running:
 
 - `narratio run`
 - `narratio plan`
@@ -20,6 +21,8 @@ Behavior:
 - strict YAML decode is enabled (`KnownFields(true)`): unknown fields fail.
 - session templates render before session YAML decode.
 - defaults are applied for optional pipeline fields.
+- campaign-level stable input paths fill missing session input paths.
+- session-level stable input paths override campaign-level input paths.
 - validation enforces required fields, value formats, and cross-field constraints.
 
 ## 2. Config file discovery
@@ -32,6 +35,15 @@ Pipeline config lookup for `run`, `plan`, `resume`, `run-stage`, and `restore`:
   2. `/etc/narratio/pipeline.yml`
 - first existing file wins.
 
+Campaign config lookup for `run`, `plan`, `resume`, `run-stage`, and `restore`:
+
+- if `--campaign <path>` is provided, that path is used.
+- if omitted, Narratio searches in order:
+  1. `./campaign.yml`
+  2. `/usr/local/etc/narratio/campaign.yml`
+  3. `/etc/narratio/campaign.yml`
+- first existing file wins.
+
 ## 3. Session file discovery and templating
 
 Session config lookup for `run`, `plan`, `resume`, `run-stage`, and `restore`:
@@ -71,20 +83,28 @@ Why this is sufficient:
 
 ## 5. Minimal session template
 
+`campaign.yml`:
+
 ```yaml
-session_id: "{{ session_id }}"
 campaign: sample-campaign
+inputs:
+  speakers_file: ./speakers.yml
+  autocorrect_file: ./autocorrect.yml
+  glossary_file: ./glossary.yml
+```
+
+`session.yml`:
+
+```yaml
+session_id: "{{ session_id }}"
 inputs:
   audio_dir: ./audio
-  speakers_file: ./examples/speakers.yml
-  autocorrect_file: ./examples/autocorrect.yml
-  glossary_file: ./examples/glossary.yml
 ```
 
 Usage:
 
 ```bash
-narratio run --config /path/to/pipeline.yml --session ./session.yml --session-id 2026-05-03
+narratio run --config /path/to/pipeline.yml --campaign ./campaign.yml --session ./session.yml --session-id 2026-05-03
 ```
 
 Previous-session-enabled variant:
@@ -92,16 +112,12 @@ Previous-session-enabled variant:
 ```yaml
 session_id: "{{ session_id }}"
 previous_session_id: "{{ previous_session_id }}"
-campaign: sample-campaign
 inputs:
   audio_dir: ./audio
-  speakers_file: ./examples/speakers.yml
-  autocorrect_file: ./examples/autocorrect.yml
-  glossary_file: ./examples/glossary.yml
 ```
 
 ```bash
-narratio run --config /path/to/pipeline.yml --session ./session.yml --session-id 2026-05-03 --previous-session-id 2026-04-26
+narratio run --config /path/to/pipeline.yml --campaign ./campaign.yml --session ./session.yml --session-id 2026-05-03 --previous-session-id 2026-04-26
 ```
 
 ## 6. Production-oriented config
@@ -158,7 +174,7 @@ Operational notes:
 - archive promotion is explicit and source-based via `archive.promote_artifacts`.
 - `source` is required; `dest` is optional and derived when omitted.
 - Narratio does not auto-promote all generated analyze artifacts.
-- `restore` reads the same config/session inputs and restore scope is bounded by committed archive current state.
+- `restore` reads the same config/campaign/session inputs and restore scope is bounded by committed archive current state.
 
 ## 7. Full pipeline reference
 
@@ -299,21 +315,34 @@ Restore-related implications:
 - restore remote identity requires archive S3 identity to resolve (`pipeline.storage.s3.bucket` and session prefix derivation inputs).
 - restore scope considers committed current state and durable paths (`manifest.json`, `transcripts/**`, `artifacts/**`, `previous/**`, optional `audio/**`).
 
-## 8. Full session reference
+## 8. Full campaign reference
+
+| Path | Type | Required | Default |
+| --- | --- | --- | --- |
+| `campaign.campaign` | string | Yes | none |
+| `campaign.inputs.speakers_file` | string | Yes | none |
+| `campaign.inputs.autocorrect_file` | string | Yes | none |
+| `campaign.inputs.glossary_file` | string | Yes | none |
+
+Campaign input paths may be absolute or relative. Relative paths resolve from the directory containing `campaign.yml`.
+
+## 9. Full session reference
 
 | Path | Type | Required | Default |
 | --- | --- | --- | --- |
 | `session.session_id` | string | Yes | none |
 | `session.previous_session_id` | string | No | empty |
-| `session.campaign` | string | Yes | none |
+| `session.campaign` | string | No | `campaign.campaign` |
 | `session.date` | string | No | empty |
 | `session.title` | string | No | empty |
 | `session.inputs.audio_dir` | string | Conditional | empty |
 | `session.inputs.audio_files[]` | list[string] | Conditional | empty |
 | `session.inputs.audio_s3.prefix` | string | Conditional | none |
-| `session.inputs.speakers_file` | string | Yes | none |
-| `session.inputs.autocorrect_file` | string | Yes | none |
-| `session.inputs.glossary_file` | string | Yes | none |
+| `session.inputs.speakers_file` | string | No | `campaign.inputs.speakers_file` |
+| `session.inputs.autocorrect_file` | string | No | `campaign.inputs.autocorrect_file` |
+| `session.inputs.glossary_file` | string | No | `campaign.inputs.glossary_file` |
+
+Session input paths may be absolute or relative. Relative audio paths and session-level stable input overrides resolve from the directory containing `session.yml`. If both `campaign.yml` and `session.yml` specify campaign identity, the values must match.
 
 Audio-source rule:
 
@@ -328,7 +357,7 @@ Previous-session rule:
 - if `session.previous_session_id` is set, it must not equal `session.session_id`.
 - canonical previous-session sources (`narratio.previous_session.artifact.<name>`) are hydrated during `prepare` from archive current state when required by enabled configured artifacts.
 
-## 9. Secrets
+## 10. Secrets
 
 Narratio supports filesystem-based secret injection via `pipeline.secrets.env_dir`.
 
@@ -347,13 +376,14 @@ Guidance:
 - do not put secret values directly in YAML.
 - configure env var names in config and provide values via env/secrets files.
 
-## 10. Examples
+## 11. Examples
 
 Maintained examples:
 
 - `examples/pipeline.minimal.yml`
 - `examples/pipeline.production.yml`
 - `examples/pipeline.full.annotated.yml`
+- `examples/campaign.yml`
 - `examples/session.template.yml`
 - `examples/session.local-audio.yml`
 - `examples/session.s3-audio.yml`