feat: Phase 0+1 — repo sync, pino, lint fixes, core components

Phase 0:
- Synced latest live-status.js from workspace (9928 bytes)
- Fixed 43 lint issues: empty catch blocks, console statements
- Added pino dependency
- Created src/tool-labels.json with all known tool mappings
- make check passes

Phase 1 (Core Components):
- src/config.js: env-var config with validation, throws on missing required vars
- src/logger.js: pino singleton with child loggers, level validation
- src/circuit-breaker.js: CLOSED/OPEN/HALF_OPEN state machine with callbacks
- src/tool-labels.js: exact/prefix/regex tool->label resolver with external override
- src/status-box.js: Mattermost post manager (keepAlive, throttle, retry, circuit breaker)
- src/status-formatter.js: pure SessionState->text formatter (nested, compact)
- src/health.js: HTTP health endpoint + metrics
- src/status-watcher.js: JSONL file watcher (inotify, compaction detection, idle detection)

Tests:
- test/unit/config.test.js: 7 tests
- test/unit/circuit-breaker.test.js: 12 tests
- test/unit/logger.test.js: 5 tests
- test/unit/status-formatter.test.js: 20 tests
- test/unit/tool-labels.test.js: 15 tests

All 59 unit tests pass. make check clean.

src/status-formatter.js

@@ -0,0 +1,142 @@
+'use strict';
+
+/**
+ * status-formatter.js — Pure function: SessionState -> formatted Mattermost text.
+ *
+ * Output format:
+ *   [ACTIVE] main | 38s
+ *   Reading live-status source code...
+ *     exec: ls /agents/sessions [OK]
+ *   Analyzing agent configurations...
+ *     Sub-agent: proj035-planner
+ *       Reading protocol...
+ *       [DONE] 28s
+ *   [DONE] 53s | 12.4k tokens
+ */
+
+const MAX_STATUS_LINES = parseInt(process.env.MAX_STATUS_LINES, 10) || 20;
+const MAX_LINE_CHARS = 120;
+
+/**
+ * Format a SessionState into a Mattermost text string.
+ *
+ * @param {object} sessionState
+ * @param {string} sessionState.sessionKey
+ * @param {string} sessionState.status - 'active' | 'done' | 'error' | 'interrupted'
+ * @param {number} sessionState.startTime - ms since epoch
+ * @param {Array<string>} sessionState.lines - Status lines (most recent activity)
+ * @param {Array<object>} [sessionState.children] - Child session states
+ * @param {number} [sessionState.tokenCount] - Token count if available
+ * @param {string} [sessionState.agentId] - Agent ID (e.g. "main")
+ * @param {number} [sessionState.depth] - Nesting depth (0 = top-level)
+ * @returns {string}
+ */
+function format(sessionState, opts = {}) {
+  const maxLines = opts.maxLines || MAX_STATUS_LINES;
+  const depth = sessionState.depth || 0;
+  const indent = '  '.repeat(depth);
+
+  const lines = [];
+
+  // Header line
+  const elapsed = formatElapsed(Date.now() - sessionState.startTime);
+  const agentId = sessionState.agentId || extractAgentId(sessionState.sessionKey);
+  const statusPrefix = statusIcon(sessionState.status);
+  lines.push(`${indent}${statusPrefix} ${agentId} | ${elapsed}`);
+
+  // Status lines (trimmed to maxLines, most recent)
+  const statusLines = (sessionState.lines || []).slice(-maxLines);
+  for (const line of statusLines) {
+    lines.push(`${indent}  ${truncateLine(line)}`);
+  }
+
+  // Child sessions (sub-agents)
+  if (sessionState.children && sessionState.children.length > 0) {
+    for (const child of sessionState.children) {
+      const childLines = format(child, { maxLines: Math.floor(maxLines / 2), ...opts }).split('\n');
+      lines.push(...childLines);
+    }
+  }
+
+  // Footer line (only for done/error/interrupted)
+  if (sessionState.status !== 'active') {
+    const tokenStr = sessionState.tokenCount
+      ? ` | ${formatTokens(sessionState.tokenCount)} tokens`
+      : '';
+    lines.push(`${indent}  [${sessionState.status.toUpperCase()}] ${elapsed}${tokenStr}`);
+  }
+
+  return lines.join('\n');
+}
+
+/**
+ * Format elapsed milliseconds as human-readable string.
+ * @param {number} ms
+ * @returns {string}
+ */
+function formatElapsed(ms) {
+  if (ms < 0) ms = 0;
+  const s = Math.floor(ms / 1000);
+  const m = Math.floor(s / 60);
+  const h = Math.floor(m / 60);
+  if (h > 0) return `${h}h${m % 60}m`;
+  if (m > 0) return `${m}m${s % 60}s`;
+  return `${s}s`;
+}
+
+/**
+ * Format token count as compact string (e.g. 12400 -> "12.4k").
+ * @param {number} count
+ * @returns {string}
+ */
+function formatTokens(count) {
+  if (count >= 1000000) return `${(count / 1000000).toFixed(1)}M`;
+  if (count >= 1000) return `${(count / 1000).toFixed(1)}k`;
+  return String(count);
+}
+
+/**
+ * Get status icon prefix.
+ * @param {string} status
+ * @returns {string}
+ */
+function statusIcon(status) {
+  switch (status) {
+    case 'active':
+      return '[ACTIVE]';
+    case 'done':
+      return '[DONE]';
+    case 'error':
+      return '[ERROR]';
+    case 'interrupted':
+      return '[INTERRUPTED]';
+    default:
+      return '[UNKNOWN]';
+  }
+}
+
+/**
+ * Truncate a line to MAX_LINE_CHARS.
+ * @param {string} line
+ * @returns {string}
+ */
+function truncateLine(line) {
+  if (line.length <= MAX_LINE_CHARS) return line;
+  return line.slice(0, MAX_LINE_CHARS - 3) + '...';
+}
+
+/**
+ * Extract agent ID from session key.
+ * Session key format: "agent:main:mattermost:channel:abc123:thread:xyz"
+ * @param {string} sessionKey
+ * @returns {string}
+ */
+function extractAgentId(sessionKey) {
+  if (!sessionKey) return 'unknown';
+  const parts = sessionKey.split(':');
+  // "agent:main:..." -> "main"
+  if (parts[0] === 'agent' && parts[1]) return parts[1];
+  return sessionKey.split(':')[0] || 'unknown';
+}
+
+module.exports = { format, formatElapsed, formatTokens, statusIcon, truncateLine, extractAgentId };