feat(runtime): autonomous reflex — chop wood + wander + proactive movement (#8)

Closes the "bot stands on a tree doing nothing" problem reported live
when the operator launched the TUI after PR #6 landed. The reactive
chain (operator > defend > eat > sleep > idle) was passive by design:
day-time, full HP and food, no hostile within 4 m ⇒ every reflex
returned noop. The bot perched in dark-oak canopy and never moved.

Changes

runtime/actions.js:
  - chopNearestTree: find any *_log within 32 blocks, equip best axe
    (falls back to fists), path to the block, dig. Per-bot 5-min
    blacklist of unreachable log positions so we don't grind on the
    same impossible target.
  - wander: pick a random offset 6-16 blocks away and path there.
  - setMovementsForGather / setMovementsForTravel: every action that
    uses pathfinder now sets its own Movements profile (canDig=true)
    instead of inheriting whatever the previous caller left. The old
    behaviour caused chop to inherit flee's canDig=false and get stuck
    in the canopy.
  - fleeFrom now uses canDig=true too — the user observed the bot
    permanently stuck on a leaf block because escape required digging.

runtime/reflex.js:
  - new autonomousReflex between sleep and idle. Cooldown 10s. Picks
    chop when log count < 16, else wander. When chop reports "no
    reachable log within 32 blocks" we switch to wander for 60s so we
    don't re-fire chop against the same impossible position.
  - defendReflex tightened: only flee when closest is ≤8m (or ≤12m
    on low HP). Avoids the "82 distant hostiles ⇒ constant flee
    loop" pathology observed at this spawn.
  - flee cooldown: same mob name within 60s ⇒ noop, so we yield to
    other reflexes if flee keeps timing out.
  - sleepReflex retry cooldown raised 30s → 5min. Sleeping fails
    permanently if no bed is around; the short retry blocked
    autonomous behaviour every tick.
  - ctx.lastReflex now records {name, label, ts} after each
    dispatched/completed reflex so the TUI can show what the bot
    just decided.

runtime/bot.js:
  - per-tick snapshot adds lastReflex and busy fields for the TUI.
  - maybeReplyToPlayer: light canned greetings (yo/hey/hi/привет)
    to non-operators when they address the bot. 30s cooldown so we
    don't spam.

tui/tui.tsx:
  - status bar shows either "▸ busy: <label>" while an action is
    in flight, or "last reflex: <name> (<label>) Ns ago" when idle.
    Gives an at-a-glance answer to "what is the bot doing right now?"

Smoke-tested live (play.xmatic.team, 2026-05-25T13:30-13:39):
  - bot did dispatch chop tree (oak_log at 617,82,95)
  - real bug surfaced and 3-fail rule filed a proposal automatically
  - after the runtime fix, chop returns "no reachable log" gracefully
  - bot switched to wander on the next tick
  - position moved from (623.31, 85, 95.12) to (623.41, 86.02, 96.7)
    — the first observable movement in this dark-oak spawn

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

runtime/bot.js

@@ -233,6 +233,33 @@ function maybeFileProposal(label) {
 	appendDiary(`proposal filed: ${filename} (${summary})`);
 }
 
+// ---- player chat replies (non-operator) ------------------------------------
+
+// Rate-limited light replies to ordinary players. Spam guard is intentional:
+// the chat rate limit catches outbound flooding; this one prevents replying
+// to every greeting in a busy room.
+let lastPlayerReplyAt = 0;
+const PLAYER_REPLY_COOLDOWN_MS = 30_000;
+
+const GREETING_RE = /\b(hi|hello|hey|yo|sup|hola|привет|здаров|здарова|здорова|здравствуй|здравствуйте|салам)\b/i;
+
+function maybeReplyToPlayer(username, text) {
+	if (!bot) return;
+	const lower = text.trim().toLowerCase();
+	const botname = bot.username.toLowerCase();
+	const addressed = lower.includes(botname);
+	if (!addressed && !GREETING_RE.test(lower)) return;
+	const since = Date.now() - lastPlayerReplyAt;
+	if (since < PLAYER_REPLY_COOLDOWN_MS) return;
+	lastPlayerReplyAt = Date.now();
+
+	// Pick a small canned response. Non-operator chat is dialog-only by design
+	// — we don't act on player verbs, we just acknowledge presence.
+	const replies = ["yo", "hey", "hi", "привет"];
+	const reply = replies[Math.floor(Math.random() * replies.length)];
+	botChat(`${username}: ${reply}`);
+}
+
 // ---- operator chat commands ------------------------------------------------
 
 function isOperator(username) {
@@ -333,6 +360,12 @@ function connect() {
 			} catch (e) {
 				warn("operator", `handler threw: ${e.message}`);
 			}
+		} else {
+			try {
+				maybeReplyToPlayer(username, message);
+			} catch (e) {
+				warn("chat", `player reply handler threw: ${e.message}`);
+			}
 		}
 	});
 
@@ -416,6 +449,10 @@ function tick() {
 	if (bot && bot.entity) {
 		lastSnapshot = buildSnapshot(bot);
 		lastSnapshot.pendingProposals = listProposals().length;
+		lastSnapshot.lastReflex = reflexCtx.lastReflex ?? null;
+		lastSnapshot.busy = reflexCtx.busy
+			? { label: reflexCtx.currentActionLabel ?? "?" }
+			: null;
 		reflexCtx.snapshot = lastSnapshot;
 		if (!reflexPaused) {
 			const result = runTick(reflexCtx);