feat(runtime): compatibility hardening (Phase 7) (#18)

Phase 7 of plans/autonomous-survival-bot-prd.md. Five small modules
that close the recurring "shared state" and "version-pinned list"
failure modes the PRD flags in §7 and §5.4.

New:
- runtime/movement-profiles.js: named profiles (GATHER, TRAVEL, FLEE,
  BUILD, RETURN_TO_BASE) as pure descriptors via PROFILE_DEFAULTS,
  plus applyProfile(profile, bot) that hands a fresh Movements to
  pathfinder. Avoids the "flee left canDig=false on the shared
  Movements, next chop got stuck in canopy" regression.
- runtime/owned-blocks.js: JSONL ledger of blocks this bot placed/
  removed (state/<host>/owned-blocks.jsonl); isOwned({x,y,z}) for
  O(1) lookups; ensureDir() makes the parent dir lazily.
- runtime/claim-avoidance.js: classifyArea({blocks, isOwned}) returns
  player_build / natural_or_owned / insufficient_data based on
  man-made block density vs ownership ratio; shouldAvoid(area) helper.
  Designed for gather/place skills to call before touching contested
  area.
- runtime/skills/compat.test.js: runs runtime/skills/groups.js against
  real minecraft-data registries for 1.18.2, 1.20.4, 1.21.5; spot-
  checks that pale_oak_log only appears on 1.21+ etc.
- runtime/compat.test.js: 10 tests covering movement descriptors,
  isManMadeBlockName, classifyArea, owned-blocks markPlaced/dedup/
  isOwned/markRemoved.

npm test now 79/79.

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

docs/runtime.md

@@ -246,6 +246,28 @@ in-process. The package is **not** a default dep — install it explicitly
 (`npm i prismarine-viewer`) before enabling. If missing, the runtime
 logs a warning and continues.
 
+### Compatibility hardening (Phase 7)
+
+Several modules now guard against the live regressions PRD §7 Phase 7
+explicitly calls out:
+
+- **`runtime/movement-profiles.js`** — named profiles (`GATHER`,
+  `TRAVEL`, `FLEE`, `BUILD`, `RETURN_TO_BASE`) as pure descriptors;
+  `applyProfile(profile, bot)` writes a fresh `Movements` to
+  pathfinder. Stops one skill's `canDig=false` from leaking into the
+  next skill's path.
+- **`runtime/owned-blocks.js`** — JSONL ledger of blocks this bot
+  placed (and removed). `isOwned({x,y,z})` for O(1) lookups.
+  `ensureDir()` makes the dir lazily so first-write doesn't fail.
+- **`runtime/claim-avoidance.js`** — `classifyArea({blocks, isOwned})`
+  returns `player_build` / `natural_or_owned` / `insufficient_data`
+  based on man-made block density vs ownership ratio. Designed for
+  the gather/place skills to call before touching a contested area.
+- **`runtime/skills/compat.test.js`** — runs `groups.js` against real
+  `minecraft-data` registries for 1.18.2, 1.20.4, 1.21.5; verifies
+  that version-sensitive blocks (e.g. `pale_oak_log`) only appear
+  where they should.
+
 ### Self-improvement v2 (Phase 6)
 
 Two classes of proposals now land in `state/<host>/proposals/`: