feat: close last two caveman gaps

skills/tok-compress/SKILL.md
  Previously advertised in skills/tok-help/SKILL.md:32 and routed in
  hooks/tok-mode-tracker.js:58, but the SKILL.md itself was missing —
  /tok-compress invocations had no skill to load. Added. Points Claude
  at the existing `tok md` CLI (deterministic, offline) instead of
  calling out to a separate Python pipeline like caveman-compress does.

tok cheatsheet (alias: modes, quickref)
  One-shot reference card for shell users. Caveman's /caveman-help only
  served Claude Code users; shell users had to read --help output or
  wade through docs. This prints the six modes, the CLI entry points,
  skill-family mapping, activation env vars, and deactivation.

Verified twice (build + vet + test -count=1) across touched packages.

Author: Patel230

internal/commands/core/cheatsheet_cmd.go

@@ -0,0 +1,80 @@
+package core
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+
+	"github.com/lakshmanpatel/tok/internal/commands/registry"
+)
+
+var cheatsheetCmd = &cobra.Command{
+	Use:     "cheatsheet",
+	Aliases: []string{"modes", "quickref"},
+	Short:   "One-shot reference card for tok compression modes and commands",
+	Long: `Print a terse reference card covering:
+  • the six compression modes (lite/full/ultra/wenyan-*)
+  • the skill family (commit, review, compress, help)
+  • activation from env and config file
+
+Non-persistent — does not change mode or write flag files.`,
+	RunE: runCheatsheet,
+}
+
+const cheatsheetBody = `
+TOK CHEATSHEET
+==============
+
+MODES
+-----
+  lite          drop filler. keep grammar.
+  full          drop articles + filler + hedging. fragments OK. (default)
+  ultra         extreme compression. abbreviations. arrows for causality.
+  wenyan-lite   classical register, filler stripped, grammar kept.
+  wenyan-full   fragments + arrow causality + tech-term abbreviations.
+  wenyan-ultra  extreme abbreviation, no connectives, symbolic chains.
+
+  Env var:   export TOK_DEFAULT_MODE=ultra
+  Config:    ~/.config/tok/config.json  →  {"defaultMode":"lite"}
+  Resolution order: env > config file > "full"
+
+COMMANDS YOU INVOKE
+-------------------
+  tok <cmd> ...           wrap any supported CLI (git, kubectl, npm, etc.)
+  tok md <file>           compress a markdown file in place; --mode=<mode>
+  tok md <file> --restore revert a compressed file from its .original.md
+  tok commit-msg          read staged diff, emit Conventional Commits subject
+  tok review-diff         scan a diff, emit one-line review comments
+  tok learn               inspect/export the learned-rule database
+  tok savings             token-savings report
+  tok doctor              diagnose filter TOML files
+  tok cheatsheet          this card
+
+SKILL FAMILY (Claude Code plugin)
+---------------------------------
+  /tok [mode]          set persistent compression mode
+  /tok-commit          caveman-style commit-message persona
+  /tok-review          caveman-style PR-review persona
+  /tok:compress <file> invoke tok-compress skill (calls tok md)
+  /tok-help            long-form help card
+
+DEACTIVATE
+----------
+  "stop tok" / "normal mode"   or unset TOK_DEFAULT_MODE
+  /tok off                     turn off for the session
+
+MORE
+----
+  Plugin authoring:  docs/plugin-dev.md
+  Benchmarks:        evals/bench.sh
+  Source:            https://github.com/lakshmanpatel/tok
+`
+
+func runCheatsheet(cmd *cobra.Command, args []string) error {
+	fmt.Print(cheatsheetBody)
+	return nil
+}
+
+func init() {
+	registry.Add(func() { registry.Register(cheatsheetCmd) })
+}

skills/tok-compress/SKILL.md

@@ -0,0 +1,85 @@
+---
+name: tok-compress
+description: >
+  Compress natural language memory files (CLAUDE.md, todos, preferences) into tok format
+  to save input tokens. Preserves all technical substance, code, URLs, and structure.
+  Compressed version overwrites the original file. Human-readable backup saved as FILE.original.md.
+  Trigger: /tok:compress <filepath> or "compress memory file"
+---
+
+# Tok Compress
+
+## Purpose
+
+Compress natural language files (CLAUDE.md, todos, preferences) into tok-speak to
+reduce input tokens. Compressed version overwrites original. Human-readable backup
+saved as `<filename>.original.md`.
+
+## Trigger
+
+`/tok:compress <filepath>` or when user asks to compress a memory file.
+
+## Process
+
+The `tok` CLI provides this directly — no separate script or LLM call required.
+Prefer the CLI path; it's deterministic and offline.
+
+1. Resolve the absolute path of the target file.
+
+2. Run:
+
+       tok md <absolute_filepath> --mode full
+
+   Other `--mode` values: `lite`, `full` (default), `ultra`, `wenyan-lite`,
+   `wenyan-full`, `wenyan-ultra`.
+
+3. The CLI will:
+   - preserve code blocks, URLs, file paths, headings, and tables exactly
+   - compress prose lines per the selected mode
+   - write the compressed version in place
+   - back up the original as `<filename>.original.md` (only on first run)
+   - print a token-savings summary
+
+4. Report the summary to the user. Mention the backup path.
+
+## Restore
+
+To revert:
+
+    tok md <filepath> --restore
+
+This copies `<filepath>.original.md` back to `<filepath>`.
+
+## Compression Rules
+
+These are encoded in the CLI; this list is informational.
+
+### Remove
+- Articles: a, an, the
+- Filler: just, really, basically, actually, simply
+- Pleasantries: "sure", "certainly", "of course", "happy to"
+- Hedging: "it might be worth", "you could consider"
+- Redundant phrasing: "in order to" → "to", "due to the fact that" → "because"
+
+### Preserve exactly (never modify)
+- Fenced code blocks (``` blocks)
+- Inline code (`backtick`)
+- URLs and markdown links
+- File paths and shell commands
+- Headings (keep text; compress body below)
+- Tables (full rows preserved)
+- Dates, version numbers, numeric literals
+
+### Wenyan modes (CJK-aware)
+- Strips modern particles (的, 了, 吧, 呢)
+- Maps causal words to arrows (because → →, therefore → →)
+- Abbreviates common tech terms (configuration → config, function → fn)
+
+## Boundaries
+
+Refuse to compress:
+- Files under `.git/`, `node_modules/`, `vendor/`
+- Binary files (non-text)
+- Files > 10 MB (warn and ask)
+
+Report errors from the CLI exit code verbatim.