v0.8.10

Fixes

1. Snapshot iteration could read past the label set values table. label_sets_values_view indexed symbols_tables_ by key id without checking that a values table existed for it, and outside asan/unit-test builds a label name registered after a snapshot was taken could reuse over-allocated memory instead of triggering a reallocation, so the snapshot ended up reporting more keys than it had values tables. In production this crashed the Persistener while it wrote a block index, reading past the end of a values-table vector. The view now remembers the values-table count at creation time and stops traversal there (#485).
2. Freeing an already-finalized timestamp stream state could crash or corrupt memory. State::stream_data is a union holding either an open bit sequence or, once finalized, a finalized_stream_id; free_memory() cleared it unconditionally instead of checking is_finalized() like the destructor does. Freeing a state finalized earlier — e.g. by ChunkFinalizer::finalize or by another series dropping a shared reference — reinterpreted the id as a SharedPtr and crashed or freed a bogus pointer through jemalloc, surfacing as a SIGSEGV inside the cgo bridge. free_memory() now checks is_finalized() first (#484).
3. Snug composite view iterators could read past label set/label name set data during a concurrent shrink. Read-only LabelNameSet/LabelSet iterators bounded traversal by the raw item count, which could outrun the shared symbol/values data if a shrink resized it concurrently. Iterators now compute a sentinel id bounded by how much of that data is actually present (#479).
4. Data race on the item count of serialized timestamp and Gorilla streams. Concurrent access could observe a torn item count read out of a shared pointer. Timestamp and Gorilla stream serialization now carry their item count through a bit-sequence representation that stores it atomically (#473).
5. Dependency security updates. Bumped the Go module golang.org/x/mod to v0.40.0 (#475) and the web UI package nanoid to v3.3.18 (#474), picking up upstream security fixes.