feat(runtime): early-game survival curriculum + stone/craft skills (Phase 3) (#15)

Phase 3 of plans/autonomous-survival-bot-prd.md. Gives the bot a
deterministic path from empty inventory through stone-tier tools and
basic storage, without an LLM call per tick.

New:
- runtime/curriculum.js: ordered milestone chooser
  (wood.16 → wood.planks-and-sticks → wood.tools → stone.32 →
   stone.tools → food.basic → storage.chest → shelter.torch). Each
  milestone exposes isDone(inventory, snapshot) and suggest() returning
  a { skillId } plan the scheduler can dispatch via runSkill. isDone
  uses "stage reached" escapes so progress is monotonic — crafting
  planks doesn't bounce the chooser back to "gather 16 logs".
- runtime/skills/gather-stone.js: gather.stone with pickaxe-required
  precondition, blacklist on failed paths, registry-aware matching
  (stone / cobblestone / deepslate / cobbled_deepslate / andesite /
  diorite / granite).
- runtime/skills/craft.js: factory + concrete skills for craft.planks,
  craft.sticks, craft.wooden-axe/-pickaxe/-sword, craft.stone-axe/
  -pickaxe/-sword, craft.furnace, craft.chest, craft.torch (torch
  requires coal or charcoal preflight).

Tests:
- runtime/curriculum.test.js: 14 tests covering chooser ordering,
  per-milestone skill suggestion, inventoryFull threshold, monotonic
  advancement across stage transitions.
- npm test now runs the full suite: 28/28 passing.

Wiring:
- runtime/bot.js: lastSnapshot.curriculum carries the next milestone
  + suggested skill on every tick; lastSnapshot.currentMilestone
  prefers the curriculum title over the planner.md line.
- tui/tui.tsx: milestone line shows the curriculum's suggested skill
  and an [inventory full] flag when isInventoryFull fires.

Reflex.js still calls actions.js directly; wiring the scheduler to
runSkill(plan.skillId, …) lands in Phase 4.

Co-authored-by: Yuriy Mayatnikov <mayatnikov@me.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/runtime.md

@@ -204,12 +204,40 @@ Reference skills shipped today: `gather.logs`, `survive.eat`,
 `runtime/actions.js` primitives directly — porting more behaviours to
 skills lands in later phases.
 
-Run the contract + groups tests:
+Run the contract + groups + curriculum tests:
 
 ```bash
 npm test
 ```
 
+### Survival curriculum (Phase 3)
+
+`runtime/curriculum.js` exposes a deterministic early-game progression:
+
+```
+wood.16 → wood.planks-and-sticks → wood.tools →
+stone.32 → stone.tools → food.basic → storage.chest → shelter.torch
+```
+
+Each milestone has an `isDone(inventory, snapshot)` predicate and a
+`suggest(inventory, snapshot)` function that names the next skill to
+dispatch. `isDone` is stateful in the sense that reaching a later tier
+implies all earlier "gather" milestones are complete (so the bot
+doesn't loop back to "gather 16 logs" after crafting them into
+planks).
+
+The current curriculum result is on every snapshot as
+`snapshot.curriculum = { milestone, plan, inventoryFull }` so the TUI
+can show what the bot is working on and which skill should drive it.
+Wiring the scheduler to actually call `runSkill(plan.skillId, …)` in
+the reflex loop is a Phase 4 task; today the reflex still uses
+`actions.js` directly.
+
+Inventory pressure: `isInventoryFull(snapshot)` is exposed on every
+curriculum result; the TUI surfaces `[inventory full]` next to the
+milestone label so the operator can see when a deposit step is needed
+before progress continues.
+
 ### Optional: prismarine-viewer
 
 Set `VIEWER_PORT=<port>` in `.env` to launch