Remove hexai-tmux-edit popup editor featurev0.42.0

The tmux popup editor and its per-agent detection (Cursor/Amp/Aider)
added maintenance surface without enough use to justify it; Codex and
Claude Code already support external-editor mode natively via Ctrl+G.
Drops internal/tmuxedit, cmd/hexai-tmux-edit, the [tmux_edit] config
schema, the Mage build target, and all related docs/README mentions.

Bump version to 0.42.0.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

1 files changed, 0 insertions, 2 deletions

diff --git a/.gitignore b/.gitignore
index 3b8714e..1c4e03b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,7 +5,6 @@
 /hexai-lsp-server
 /hexai-mcp-server
 /hexai-tmux-action
-/hexai-tmux-edit
 /bin/
 
 # Coverage artifacts (mage coverage, mage covercheck)
@@ -14,7 +13,6 @@ docs/coverage.html
 docs/coverage/
 
 # Temp/scratch files
-.tmux-edit-send.*.md
 /.local/
 /.gomodcache/
 /*.out