[rust-axum] Prevent multiple declarations of the same operation

[rgroothuijsen]

If tags are defined for an operation, the router path will be duplicated per tag. If a security schema is defined as well, the code will no longer compile because there will be duplicate operations with and without a claims parameter. Since there doesn't appear to be a benefit to specifying the same operation multiple times, this skips adding an operation if it already exists.

Fixes #21144

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[wing328]

thanks for the pr

cc @linxGnu

[linxGnu]

Almost LGTM.

Could you please re-run integration test with following commands:

./bin/generate-samples.sh bin/configs/manual/rust-axum-*
mvn integration-test -f samples/server/petstore/rust-axum/pom.xml

[wing328]

Could you please re-run integration test with following commands:

did these locally and the result is good

    Finished `dev` profile [unoptimized + debuginfo] target(s) in 28.32s
[INFO]
[INFO] --- exec:1.2.1:exec (fmt) @ RustServerTests ---
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  02:43 min
[INFO] Finished at: 2025-06-16T10:34:01+08:00
[INFO] ------------------------------------------------------------------------
[INFO] 5 goals, 5 executed

[wing328]

FYI. another way to address similar issue is to use the operationIdNameMappings option

ref: https://github.com/openapitools/openapi-generator/blob/master/docs/customization.md#name-mapping