Document extraction reference support

docs/cli.md

@@ -63,6 +63,42 @@ declares that slot. Bound reference files are read before extraction, validated
 as UTF-8 text, and passed only to the lane extractor that declares the slot.
 Reference content is not written to diagnostics, logs, errors, or manifests.
 
+Reference binding precedence is:
+
+1. pipeline-level config `references`;
+2. lane-level config `references`;
+3. `--reference` run flags;
+4. `--without-reference` run flags.
+
+`--reference` binds or replaces one slot for one selected lane. Use
+`slot=path` when the selected lanes declare the slot unambiguously:
+
+```sh
+go run ./cmd/notarius run dnd-session \
+  --config examples/dnd-spells.config.yml \
+  --input examples/seriatim-minimal-transcript.json \
+  --reference roster=./campaign-roster.txt
+```
+
+Use `lane.slot=path` when multiple selected lanes declare the same slot or when
+you want to target a specific lane:
+
+```sh
+go run ./cmd/notarius run dnd-session \
+  --config examples/dnd-spells.config.yml \
+  --input examples/seriatim-minimal-transcript.json \
+  --reference spells.glossary=./campaign-glossary.txt
+```
+
+Use `--without-reference` to remove a configured optional binding for a run:
+
+```sh
+go run ./cmd/notarius run dnd-session \
+  --config examples/dnd-spells.config.yml \
+  --input examples/seriatim-minimal-transcript.json \
+  --without-reference glossary
+```
+
 For durable output, diagnostics, retention, and failure inspection, see
 [Operations](operations.md).