feat: v0.9.5 context in tokens as well as percent

Claude's footer reads "ctx 34% 346k/1M"; the Sessions panel and the
session switcher use the same label via ctxLabel(). Closes #43

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WHRLCCdXYm41Qx5kNhehaP

libexec/devdesk-statusline

@@ -43,16 +43,20 @@ if [[ $session =~ ^[A-Za-z0-9][A-Za-z0-9_-]{0,63}$ ]]; then
     fi
 fi
 
-# Footer line: session · model · context % · plan use. ANSI colour numbers, not
+# Footer line: session · model · context % and tokens · plan use. ANSI colour numbers, not
 # RGB, so the browser's dark or light palette applies (devdesk#31). Claude sends
 # rate_limits only to Pro/Max subscribers; there .cost is an API-price estimate,
 # not a bill, so show the 5-hour plan use instead and keep $ for API-key billing.
 jq -rM --arg s "$session" '
     def c($sgr; $t): "\u001b[\($sgr)m\($t)\u001b[0m";
     def pct: if . == null then "—" else "\(. | floor)%" end;
+    def tok: if . >= 1000000 then "\(. / 100000 | round / 10)M" elif . >= 1000 then "\(. / 1000 | round)k" else "\(.)" end;
+    def ctxtok: .context_window | (.current_usage | if . then (.input_tokens // 0) + (.cache_creation_input_tokens // 0)
+        + (.cache_read_input_tokens // 0) else null end) as $u
+        | if $u == null then "" else " \($u | tok)\(if .context_window_size then "/\(.context_window_size | tok)" else "" end)" end;
     [ (if $s != "" then c("33"; "◈ \($s)") else empty end),
       c("36"; .model.display_name // "Claude"),
-      c("37"; "ctx \(.context_window.used_percentage | pct)"),
+      c("37"; "ctx \(.context_window.used_percentage | pct)\(ctxtok)"),
       (if .rate_limits.five_hour.used_percentage != null
        then c("37"; "5h \(.rate_limits.five_hour.used_percentage | pct)")
        else c("37"; "$\((.cost.total_cost_usd // 0) * 100 | round / 100)") end)