* fix: resolve clippy warnings across workspace
* ci: also run clippy on rmcp with all features except local
--all-features enables the local feature, which cfg-gates out
tower.rs and most of the test suite, so the existing clippy step
never actually lints them.
* feat: implement SEP-2164 resource not found errors
* test: update protocol version utility expectations
* feat: gate not-found code at server boundary
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Co-authored-by: Michael Neale <michael.neale@gmail.com>
* feat: add support for custom HTTP headers in StreamableHttpClient
* feat: implement reserved header checks for custom HTTP headers in StreamableHttpClient