Update docs and set version to v3.2.1

Author: chad-earthscope

ChangeLog

@@ -1,11 +1,13 @@
-Unreleased:
+2025.354: v3.2.1
   - Rename ms3_mstl_init_fd() to ms3_msfp_init_fd() and add backward compatibility.
   - Add -fPIC to the build options for the static library target.
   - Update internal selection matching to support `!` in addition to `^` for
   character class negation and handle edge cases more robustly.
   - Avoid modifying record buffer during v3 CRC check and add CRC validation to testing.
   - Add v3 parsing test for ensuring header-indicated lengths are sane.
   - Small fixes of logic errors and increased portability.
+  - Add GitHub action to build and test on multiple platforms.
+  - Fix Windows symbol issues and CMake configuration.
 
 2025.315: v3.2.0
   - Add generator-style packing interfaces for MS3Record and MS3TraceList.

libmseed.h

@@ -29,8 +29,8 @@ extern "C"
 {
 #endif
 
-#define LIBMSEED_VERSION "3.2.0"   //!< Library version
-#define LIBMSEED_RELEASE "2025.315" //!< Library release date
+#define LIBMSEED_VERSION "3.2.1"    //!< Library version
+#define LIBMSEED_RELEASE "2025.354" //!< Library release date
 
 /** @defgroup io-functions File and URL I/O */
 /** @defgroup miniseed-record Record Handling */