feat: add portable Claude Code statusline kit

Replicating the cship-based statusline across machines meant manually
copying three files and hand-editing settings.json with per-user absolute
paths — error-prone and slow. Bundling the assets with an idempotent
installer that resolves the pwsh path at runtime and merges into an
existing settings.json makes rollout a single command per PC.

assets/cship.toml

@@ -0,0 +1,52 @@
+# cship — Claude Code statusline (Hero / Recommended + usage progress bars)
+# Reference: https://cship.dev
+[cship]
+lines = [
+  "$starship_prompt",
+  "$cship.model $cship.effort $cship.context_window.total_input_tokens $cship.context_bar $cship.peak_usage $cship.usage_limits",
+]
+
+[cship.model]
+symbol = "🤖 "
+style  = "bold cyan"
+
+[cship.effort]
+symbol      = "⚡ "
+style       = "fg:#7dcfff"
+high_style  = "fg:#e0af68"
+xhigh_style = "bold fg:#e0af68"
+max_style   = "bold fg:#f7768e"
+
+[cship.context_bar]
+symbol             = "🧠 "
+filled_char        = "█"
+empty_char         = "░"
+format             = "[$symbol$value]($style)"
+width              = 10
+style              = "fg:#7dcfff"
+warn_threshold     = 40.0
+warn_style         = "yellow"
+critical_threshold = 70.0
+critical_style     = "bold red"
+
+# $value is emitted inside a §T§…§ marker so the statusline wrapper can
+# compact the raw token count (e.g. 42329 → 42.3K) before display.
+[cship.context_window.total_input_tokens]
+symbol = "🔢 "
+style  = "fg:#a9b1d6"
+format = "[$symbol§T§$value§]($style)"
+
+# usage_limits emits machine markers (§TYPE§pct§reset§); the statusline wrapper
+# turns them into progress bars styled like context_bar. Thresholds >100 so cship
+# adds no ANSI of its own around the markers.
+[cship.usage_limits]
+style              = ""
+separator          = "   "
+five_hour_format   = "§5§{pct}§{reset}§"
+seven_day_format   = "§7§{pct}§{reset}§"
+warn_threshold     = 101
+critical_threshold = 101
+
+[cship.peak_usage]
+symbol = "⏰ "
+style  = "fg:#e0af68"