Add Claude status line script

dir | git branch | model | tokens-in-context status line, symlinked
from ~/.claude/statusline.sh per the portability protocol.

adapters/claude/statusline.sh

@@ -0,0 +1,63 @@
+#!/usr/bin/env bash
+# ~/.claude/statusline.sh
+# Claude Code status line: dir | git branch | model | token count
+
+input=$(cat)
+
+# 1. Current directory (abbreviate $HOME to ~)
+cwd=$(printf '%s' "$input" | jq -r '.workspace.current_dir // .cwd // empty' 2>/dev/null)
+if [ -z "$cwd" ]; then
+  cwd="$PWD"
+fi
+cwd="${cwd/#$HOME/\~}"
+
+# 2. Git branch (if in a git repo)
+branch=""
+if command -v git >/dev/null 2>&1; then
+  branch=$(git -C "${cwd/#\~/$HOME}" rev-parse --abbrev-ref HEAD 2>/dev/null)
+  [ "$branch" = "HEAD" ] && branch=$(git -C "${cwd/#\~/$HOME}" rev-parse --short HEAD 2>/dev/null)
+fi
+
+# 3. Model display name
+model=$(printf '%s' "$input" | jq -r '.model.display_name // empty' 2>/dev/null)
+
+# 4. Token count from transcript JSONL
+ctx=""
+transcript=$(printf '%s' "$input" | jq -r '.transcript_path // empty' 2>/dev/null)
+if [ -n "$transcript" ] && [ -r "$transcript" ] && command -v jq >/dev/null 2>&1; then
+  raw=$(grep -o '"usage":{[^}]*}' "$transcript" 2>/dev/null | tail -1)
+  if [ -n "$raw" ]; then
+    total=$(printf '%s' "{$raw}" | jq -r '
+      .usage |
+      ((.input_tokens // 0)
+       + (.cache_read_input_tokens // 0)
+       + (.cache_creation_input_tokens // 0)
+       + (.output_tokens // 0))
+    ' 2>/dev/null)
+    if [ -n "$total" ] && [ "$total" -gt 0 ] 2>/dev/null; then
+      if [ "$total" -ge 1000 ]; then
+        ctx=$(awk "BEGIN { printf \"%.1fk ctx\", $total/1000 }")
+      else
+        ctx="${total} ctx"
+      fi
+    fi
+  fi
+fi
+
+# Assemble the line, separating non-empty segments with " | "
+parts=()
+[ -n "$cwd" ]    && parts+=("$cwd")
+[ -n "$branch" ] && parts+=("$branch")
+[ -n "$model" ]  && parts+=("$model")
+[ -n "$ctx" ]    && parts+=("$ctx")
+
+joined=""
+for part in "${parts[@]}"; do
+  if [ -z "$joined" ]; then
+    joined="$part"
+  else
+    joined="$joined | $part"
+  fi
+done
+
+printf '%s' "$joined"