Add the metadata pub.dev scores a package on

description, repository, issue_tracker and topics, plus a changelog,
which between them are most of a package's discoverability. The
repository URLs are a guess at the new home and want checking before the
first publish.

publish_to stays none so an accidental publish from inside this checkout
cannot succeed. Remove it in the new repository.

Version 0.1.0 rather than 0.0.1: a published version can be retracted
but never deleted, so the first one should mean something.

CHANGELOG.md

@@ -0,0 +1,30 @@
+# Changelog
+
+## 0.1.0
+
+First release.
+
+A zstd decompressor in plain Dart. Decompression only, native platforms only,
+one frame per call.
+
+- Decodes RFC 8878 frames: raw, RLE and compressed blocks; raw, RLE, compressed
+  and treeless literals in one-stream and four-stream form; Huffman weights in
+  both the direct nibble and FSE-coded forms; predefined, RLE, FSE and repeat
+  sequence tables for all three symbols; repeated offsets including the
+  no-literals shift; multi-block frames reusing an earlier block's tables.
+- Verifies the content checksum when a frame carries one, with XXH64 in
+  `lib/src/xxhash.dart`.
+- Refuses dictionaries, several frames in one buffer, and any input left over
+  after a frame.
+- Bounds what a frame header can make it allocate. `ZstdDecoder` takes a
+  `maxOutputSize`, 64 MiB by default, and a caller passing `expectedSize` gets
+  an exact check against the frame's own declared size.
+- Every failure is a `ZstdException`.
+
+Correctness is measured against libzstd through pyzstd rather than against
+expectations written by hand: 2,615 blocks of real elevation data across 32
+containers, plus a committed corpus of 24 fixtures covering the format branches
+that real data never reaches. 103 tests.
+
+Roughly four times slower than native zstd. On a Pixel 10 Pro XL, profile AOT,
+a 128 KiB block decodes in 0.414 ms, which is 302 MB/s.