fix(mermaid): switch to crates.io and patch dagre_rust panic

Switch mermaid-rs-renderer from git dependency to crates.io 0.1.

Vendor and patch dagre_rust 0.0.5 to fix upstream panic in
remove_edge_label_proxies() where unwrap() is called on None
when processing edge label proxies without edge references.

This enables sequence diagrams and state diagrams that previously
crashed the build.

patches/dagre_rust/.cargo_vcs_info.json

@@ -0,0 +1,6 @@
+{
+  "git": {
+    "sha1": "62c894d556f29ddc2c4f97047e511907290a56d3"
+  },
+  "path_in_vcs": ""
+}