chore: apply cargo fmt across workspace and update docs

- Run cargo fmt on all Rust crates for consistent formatting
- Update CLAUDE.md with WASM plugin commands and dev.ps1 instructions
- Update wiki: add WASM plugin architecture, rewrite dev environment docs
- Minor frontend cleanup (unused imports)

crates/erp-server/migration/src/m20260411_000003_create_user_credentials.rs

@@ -25,7 +25,11 @@ impl MigrationTrait for Migration {
                             .not_null()
                             .default("password"),
                     )
-                    .col(ColumnDef::new(UserCredentials::CredentialData).json().null())
+                    .col(
+                        ColumnDef::new(UserCredentials::CredentialData)
+                            .json()
+                            .null(),
+                    )
                     .col(
                         ColumnDef::new(UserCredentials::Verified)
                             .boolean()