Bilterm v3.0.4 — agent.wait non-blocking, macOS verify.sh, Linux release script

Bug-fix and tooling release. Thanks to @kitsumiko for the agent.wait, macOS verify.sh and docs fixes.

Fixed

• agent.wait no longer blocks the JSON-RPC server (#26). Previously, a client waiting for an agent message stopped every other client's requests until the wait ended, which took up to 10 s. Waits that have no message yet are now parked and checked every 50 ms while the serve loop keeps handling other requests. This applies to the Unix-socket, TCP and HTTP endpoints. The 10 s timeout cap is unchanged, and at most 64 waits can be parked at once.
• scripts/verify.sh runs under macOS /bin/bash 3.2 (#25). It no longer uses mapfile, empty arrays no longer trip set -u, an unknown --only group or --tier exits 2, and the summary line no longer picks up the extra spaces BSD wc -l adds. The macOS CI job is green again and is now a required check.

Changed

• scripts/build-release-assets.sh builds only the Linux targets, and builds the tag (#24). It used to try to cross-link the macOS targets, which fails without the Apple SDK, so it aborted before packaging anything. It also copied its windows-gnu zip over the bilterm-x86_64-pc-windows-msvc.zip alias, which an upload would have used to replace the native Windows installer. macOS and Windows archives come from the release-binaries workflow. The script now builds the tag in a clean worktree, and adds --upload, which merges its checksums into the release's SHA256SUMS, and --no-build.

Documentation

• Current-version references are back in sync with Cargo.toml: README badge, docs hub, user guide, man page, flake.nix and API examples (#27).
• Fixed the secure_fs path in CLAUDE.md, AGENTS.md and the docs. It is src/secure_fs.rs, not src/util/secure_fs.rs (#27).