Unify installer colors with vim/shell palette and clean up output

- Replace BLUE/CYAN/CYAN_BOLD with TEAL/TEAL_BOLD (#2CB494) to match
  the primary accent used across vim, zsh prompt, tmux, and fzf
- Update BLUE (#0C48CC -> #4068D4) then merge into TEAL
- Update RED (#F40404 -> #F88C14) to match vim/shell error orange
- Rename GREEN to grey-blue (#7290B8) for [PASS] messages
- Format all raw echo output with log functions or log_quote
- Suppress sudo prompt when credentials are already cached
- Add missing log_pass to 22-zsh.sh and 23-stow.sh
- Convert raw 'already installed' echos to log_skip (7 scripts)
- Pipe SSH key and mise output through log_quote
- Suppress noisy bat cache and mise WARN output
- Match fastfetch colors to palette (teal logo, grey-blue keys)

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

install.d/10-brew.sh

@@ -9,11 +9,11 @@
 [[ "$DOTS_OS" != "macos" ]] && { log_skip "Not macOS"; return 0; }
 
 if ! command -v brew &> /dev/null; then
-    echo "Installing Homebrew..."
+    log_info "Installing Homebrew..."
     bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
     eval "$(/opt/homebrew/bin/brew shellenv)"
 else
-    echo "Homebrew is already installed."
+    log_skip "Homebrew already installed"
 fi
 brew --version | log_quote
 log_pass "Homebrew installed"