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Assisted-by: GLM 5.3

internal/markdown/testdata/corpus/mermaid.md

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+# Diagrams
+
+A flowchart of the observed cycle:
+
+```mermaid
+flowchart LR
+    A[Observation] --> B{Hypothesis}
+    B -->|confirmed| C[Theory]
+    B -->|refuted| D[Revised model]
+```
+
+A sequence of a measurement:
+
+```mermaid
+sequenceDiagram
+    participant O as Observer
+    participant S as Source
+    O->>S: request spectrum
+    S-->>O: redshifted light
+    Note over S: proper time runs slow
+```
+
+A type the renderer does not carry stays source:
+
+```mermaid
+stateDiagram-v2
+    [*] --> calm
+```