ci: avoid commit changes on push

[tcrypt25519]

Split CI so push builds run fmt/clippy/tests without auto-committing back to protected branches. Keep shared check-rust action for PRs only.

[semanticdiff-com]

Review changes with  

Changed Files

File	Status
src/adapter/solana.rs	22% smaller
.github/workflows/ci.yml	1% smaller
src/message.rs	0% smaller
tests/solana_flow.rs	0% smaller

[gemini-code-assist]

Note

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