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, 17 deletions

diff --git a/internal/appconfig/config_merge.go b/internal/appconfig/config_merge.go
index f3557c1..e5ad6a5 100644
--- a/internal/appconfig/config_merge.go
+++ b/internal/appconfig/config_merge.go
@@ -10,7 +10,6 @@ func (a *App) mergeWith(other *App) {
 	a.mergeProviderFields(other)
 	a.mergeSurfaceModels(other)
 	a.mergePrompts(other)
-	a.mergeTmuxEdit(other)
 	a.mergeTmuxAction(other)
 }
 
@@ -237,19 +236,3 @@ func (a *App) mergeTmuxAction(other *App) {
 		a.TmuxActionMenu = append([]TmuxActionMenuEntry{}, other.TmuxActionMenu...)
 	}
 }
-
-// mergeTmuxEdit copies non-empty tmux edit settings from other.
-func (a *App) mergeTmuxEdit(other *App) {
-	if s := strings.TrimSpace(other.TmuxEditPopupWidth); s != "" {
-		a.TmuxEditPopupWidth = s
-	}
-	if s := strings.TrimSpace(other.TmuxEditPopupHeight); s != "" {
-		a.TmuxEditPopupHeight = s
-	}
-	if s := strings.TrimSpace(other.TmuxEditDefaultAgent); s != "" {
-		a.TmuxEditDefaultAgent = s
-	}
-	if len(other.TmuxEditAgents) > 0 {
-		a.TmuxEditAgents = append([]TmuxEditAgentCfg{}, other.TmuxEditAgents...)
-	}
-}