feat: new parser for mention everything (#411)

* feat: implement custom parser for mentions

* feat: handle backticks in codeblocks and escapes

* chore: remove fancy-regex

* fix: dont serialise empty role mentions

* chore: cleanup role mentions logic

* chore: update lockfile

* fix: actually use everyone and online mentions from content

* fix: broken merge

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Signed-off-by: Zomatree <me@zomatree.live>

crates/core/models/Cargo.toml

@@ -25,7 +25,6 @@ revolt-permissions = { version = "0.8.4", path = "../permissions" }
 
 # Utility
 regex = "1.11"
-fancy-regex = "0.14"
 indexmap = "1.9.3"
 once_cell = "1.17.1"
 num_enum = "0.6.1"