Rust wrapper: add one-shot XChaCha20-Poly1305 encrypt/decrypt functions

[holtrop-wolfssl]

Description

Rust wrapper: add one-shot XChaCha20-Poly1305 encrypt/decrypt functions

Testing

CI / unit tests

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation

[holtrop-wolfssl]

retest this please (org.jenkinsci.plugins.workflow.actions.ErrorAction$ErrorId: 6493d207-3f8e-4bc5-8da5-109f99226a50
org.jenkinsci.plugins.workflow.support.steps.AgentOfflineException: Unable to create live FilePath for wolf-linux-cloud-node-aw79sv)

[devin-ai-integration]

🛟 Devin Lifeguard found 1 likely issues in this PR

• do-not-change-external-apis snippet: Keep the original wc_XChaCha20Poly1305_Init(...) prototype unchanged and add a new function (e.g., wc_XChaCha20Poly1305_Init_ex(...)) with the desired (nonce, nonce_len, key, key_len) order, having the old function call the new one after shuffling its parameters.

@holtrop-wolfssl
please take a look at the above issues which Devin flagged. Devin will not fix these issues automatically.