feat(herdr-tmux): Release plugin and standalone CLI 0.1.0

[Unique-Divine]

Release herdr-tmux 0.1.0 as a Herdr plugin and Cargo CLI

Add registered layout actions and popup pickers while preserving the standalone CLI. Prepare matching Cargo and plugin versions for the source-built release herdr-tmux/v0.1.0.

Related to #24. Its broader requirements remain open; user configuration and styling are tracked by #59 and #60.

Rationale

Plugin popups have no underlying pane ID in their shell identity. The picker must recover the originating tab and pane from Herdr invocation context to select the correct target. Cargo users also need registration that points at their installed executable without rebuilding it.

Key Changes

1. Register four actions and two popup entrypoints for Herdr 0.9.5 or later. Migrate the managed bindings to plugin actions.
2. Resolve explicit CLI targets before plugin context, then fall back to shell identity. Keep direct layout and picker commands available.
3. Add plugin register with an executable-backed manifest, conflict detection, and manifest restoration when registration fails.
4. Add version reporting, locked package checks on Linux and macOS, release documentation, and the scoped tag convention.
5. Render the agent picker with aligned headings, status colors and icons, compact tab labels, and width-aware title truncation.

1 - Distribution

Both cargo install herdr-tmux --version 0.1.0 --locked and herdr plugin install Unique-Divine/dotfiles/herdr-tmux --ref herdr-tmux/v0.1.0 build from source and require Rust and Cargo. This release supports Linux and macOS. Prebuilt binaries, configurable popup behavior, and configurable styling remain follow-up work.