chore(release): 0.4.0

[github-actions]

The next claudecode.nvim release. Merging this PR creates the release tag and GitHub Release, then starts Communique GitHub Release note generation.

[0.4.0] - 2026-06-25

Added

• :checkhealth claudecode health check that verifies your Neovim version, setup(), the Claude CLI, terminal provider, WebSocket server, lock file, and live connection state, with actionable advice on each failure (#275).
• :ClaudeCodeSendText {text} command (and require("claudecode.terminal").send_to_terminal(text, opts)) to send arbitrary text to the open Claude terminal as if typed at the prompt; :ClaudeCodeSendText! inserts without submitting. Multi-line text is sent via bracketed paste. Works with the in-editor native/snacks providers only (#272).
• User ClaudeCodeSendComplete autocmd, fired once per file when a send is accepted while Claude is connected, with data = { file_path, start_line, end_line, context } (lines 0-indexed). Lets you run post-send logic such as focusing a Claude session running outside Neovim (provider = "none"/"external"), e.g. via tmux select-pane (#265).
• User ClaudeCodeDiffOpened / ClaudeCodeDiffClosed autocmds carrying a data payload (tab/window/file info), so configs can react to diffs opening and closing — resize, relayout, statusline, etc. (#270, #297).
• :ClaudeCodeCloseAllDiffs command to close pending Claude diffs at once; accepted-but-unwritten diffs are left intact so saved edits are never discarded (#261).
• diff_opts.layout = "unified": a unified diff rendered in a single buffer with deleted (red/strikethrough) and added (green) lines interleaved, a compact alternative to the two-pane "vertical"/"horizontal" layouts. Requires Neovim >= 0.9.0; the ClaudeCodeInlineDiffAdd/Delete/AddSign/DeleteSign highlight groups are customizable (#195, #295).
• terminal.auto_insert option (default true) controlling whether the Claude terminal auto-enters insert/terminal mode on focus; set auto_insert = false to stay in Normal mode and preserve your scroll position (#233).
• terminal.diff_split_width_percentage (optional terminal width while a diff is open, falling back to split_width_percentage) and diff_opts.auto_resize_terminal (default true; set false to own the layout yourself) (#270).
• :ClaudeCodeTreeAdd and :ClaudeCodeSend now support snacks.nvim pickers (snacks_picker_list), adding the selected/highlighted file(s) to Claude's context (#269).
• netrw file selection: <leader>as in netrw buffers adds marked files or the file under cursor to Claude's context (#62).
• Selection updates are now also sent on BufEnter, so switching buffers without moving the cursor still updates Claude's selection context (#159).
• Model picker refreshed: evergreen, version-free labels (Claude Opus (Latest), Claude Sonnet (Latest), Claude Haiku (Latest)), the 1M-context opus[1m]/sonnet[1m] variants, and Default (account recommended) (#256).

Fixed

• The WebSocket auth token is now generated from a cryptographically secure RNG, and the lock file is written atomically with 0600 permissions in a 0700 directory (previously world-readable 0644). Handshake auth comparison is constant-time (#259).
• Malformed WebSocket frames now close the connection with the correct RFC 6455 status code instead of leaving the connection wedged with un-drainable bytes (#258).
• A second Neovim instance no longer fails to start its server with EADDRINUSE; port binding retries across candidate ports and the per-process PRNG seed is restored (#284).
• Disconnect callbacks now fire on every teardown path (EOF, read/protocol errors, CLOSE frames, keepalive timeouts), preventing phantom clients from accumulating (#176).
• System sleep is detected (>1.5x ping interval elapsed) and client pong timestamps are reset on wake, preventing false keepalive disconnections after a laptop resumes (#141).
• closeAllDiffTabs is now scoped to claudecode's own tracked diffs and no longer wipes out an open diffview.nvim, fugitive, or native :diffsplit; openFile/openDiff no longer reuse a window in diff mode (#290).
• Rejecting a Claude diff with :q (or :close / <C-w>c / closing the tab) now resolves it as rejected via a new WinClosed autocmd (#266).
• Diffs opened via openDiff are now auto-closed when the client that opened them disconnects or the integration stops, instead of lingering forever when resolved outside this Neovim (#261).
• Diffs now open when the Claude terminal is the only window — a split is created to host the diff instead of failing with "No suitable editor window found" (#260).
• A leftover diff split is no longer left behind after accepting a diff; plugin-created windows are tracked and cleaned up deterministically (#175).
• open_in_new_tab diff setup errors no longer strand an empty tab; focus returns to the original tab (#264).
• keep_terminal_focus now works for floating Snacks terminals instead of stealing focus to the hidden diff split (#178).
• Fixed the Snacks "climbing cursor" on hide/show toggle: the panel is now parked rather than destroyed, preserving the cursor anchor Claude re-renders against (splits on all versions; floats require Neovim >= 0.10) (#271).
• The Claude terminal now adds loopback hosts (localhost, 127.0.0.1, ::1) to no_proxy/NO_PROXY, so a configured proxy no longer tunnels Claude's ws://127.0.0.1 IDE connection and times out queued @ mentions (#268).
• Worked around a Neovim core bug (< 0.12.2) that fragmented large bracketed pastes into the terminal, making Cmd+V appear to truncate content; controlled via terminal.fix_streamed_paste ("auto" default, no-op on >= 0.12.2) (#252).
• Quickly-made visual selections are now pushed to Claude reliably; selections are flushed synchronously on visual-mode exit and persist until the cursor moves (#267).
• IDE tool responses are now handled correctly: diagnostics return grouped URI-based payloads with editor-native ranges and severity names, an unsupported resources capability is no longer advertised, and background file opens preserve focus (#274).
• getDiagnostics now accepts a bare file path (not just a file:// URI), since Claude often sends the path without a scheme (#163).
• ClaudeCodeSend no longer misroutes ordinary files into tree-extraction when their path merely contains neo-tree/NvimTree; buffers are now classified by filetype only (#292).
• File paths containing $ are now handled correctly in ClaudeCodeAdd and openFile (#286).
• The legacy diff options vertical_split and open_in_current_tab are applied correctly again (they were silently ignored after a merge-order change) (#142).
• Fixed a segfault when accepting a new-file diff with render-markdown.nvim installed, by turning off diff mode before the post-write redraw (#224).
• The empty scratch buffer is now wiped when the terminal provider is none (#223).
• snacks_picker_list buffers are excluded from main-editor-window detection, so diffs no longer target the picker (#165).
• Selection-context fallback now matches the [Claude Code] terminal name via substring, so external (provider = "none") terminals correctly skip sending selection context (#160).
• Selection debounce timers are now stopped and closed safely, fixing a libuv handle leak and stale callbacks firing after being superseded (#245).
• A one-time warning is now emitted when focus_after_send = true with provider = "none"/"external", pointing at the new ClaudeCodeSendComplete event (#265).
• Bumped the Haiku picker label to 4.5 (#146).

Changed

• Floating diff terminals are no longer resized when restoring terminal widths (#178).

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Maintained by the release-please workflow. CHANGELOG.md and the release PR body are regenerated by Communique on every push to main, so manual edits to this PR are overwritten.