fix: SIGPIPE (exit 141) in mise verification, remove redundant bat script

Replace head -1 with sed -n '1p' across all install scripts to
prevent SIGPIPE when commands produce multi-line output. head closes
the pipe after reading line 1, causing the writer to receive SIGPIPE
which propagates via pipefail (exit 141). sed reads all input,
avoiding the broken pipe.

Remove install.d/26-bat.sh — bat is already installed and managed
via mise in 30-mise.sh.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

install.d/26-bat.sh

@@ -1,33 +0,0 @@
-#!/usr/bin/env bash
-
-# -----------------------------------------------------------------------------
-# Description:
-#   Install bat and build theme cache from dotfiles.
-#
-
-if ! command -v bat &> /dev/null; then
-    case "$DOTS_PKG" in
-        brew)
-            brew install bat
-            ;;
-        apt)
-            sudo apt-get install -qq bat
-            # Debian installs binary as 'batcat'; symlink to 'bat'
-            if ! command -v bat &> /dev/null && command -v batcat &> /dev/null; then
-                sudo ln -sf "$(which batcat)" /usr/local/bin/bat
-            fi
-            ;;
-        pacman)
-            sudo pacman -S --noconfirm bat
-            ;;
-        *)
-            log_warn "Skipping bat install: no supported package manager found"
-            return 0
-            ;;
-    esac
-fi
-
-bat --version | log_quote
-
-bat cache --build &>/dev/null
-log_pass "bat theme cache built"

install.d/27-preview.sh

@@ -22,7 +22,7 @@ if ! command -v chafa &> /dev/null; then
             ;;
     esac
 fi
-command -v chafa &> /dev/null && chafa --version | head -1 | log_quote
+command -v chafa &> /dev/null && chafa --version | sed -n '1p' | log_quote
 
 # pdftotext — PDF text extraction (part of poppler)
 if ! command -v pdftotext &> /dev/null; then
@@ -41,6 +41,6 @@ if ! command -v pdftotext &> /dev/null; then
             ;;
     esac
 fi
-command -v pdftotext &> /dev/null && pdftotext -v 2>&1 | head -1 | log_quote
+command -v pdftotext &> /dev/null && pdftotext -v 2>&1 | sed -n '1p' | log_quote
 
 log_pass "preview dependencies"

install.d/30-mise.sh

@@ -101,15 +101,15 @@ log_info "Verifying installations..."
         echo "node $(mise exec -- node --version)"
         echo "npm $(mise exec -- npm --version)"
         mise exec -- gh --version
-        mise exec -- terraform --version | head -1
+        mise exec -- terraform --version | sed -n '1p'
         echo "firebase: $(mise exec -- firebase --version)"
-        echo "fastfetch: $(mise exec -- fastfetch --version 2>&1 | head -1)"
+        echo "fastfetch: $(mise exec -- fastfetch --version 2>&1 | sed -n '1p')"
-        mise exec -- glow --version | head -1
+        mise exec -- glow --version | sed -n '1p'
     fi
     echo "fzf $(fzf --version)"
-    bat --version | head -1
+    bat --version | sed -n '1p'
     zoxide --version
-    rg --version | head -1
+    rg --version | sed -n '1p'
-    delta --version 2>/dev/null | head -1 || echo "delta: installed (version check failed)"
+    delta --version 2>/dev/null | sed -n '1p' || echo "delta: installed (version check failed)"
 } | log_quote
 log_pass "mise tools installed"

install.d/81-cmatrix.sh

@@ -24,5 +24,5 @@ if ! command -v cmatrix &> /dev/null; then
             ;;
     esac
 fi
-command -v cmatrix &> /dev/null && cmatrix -V 2>&1 | head -1 | log_quote
+command -v cmatrix &> /dev/null && cmatrix -V 2>&1 | sed -n '1p' | log_quote
 log_pass "cmatrix installed"