feat(diagnostics): funnel events throughout setup with persisted install-id

Shared bash + node emitter in setup/lib/diagnostics.{sh,ts} reads/writes data/install-id so every event from a single install shares one distinct_id — bash-side setup_launched/setup_start, node-side auto_started, per-step started/completed, auth_method_chosen, channel_chosen, first_chat_ready/failed, setup_incomplete, setup_aborted, setup_completed. Opt-out via NANOCLAW_NO_DIAGNOSTICS=1.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

setup/lib/diagnostics.sh

@@ -0,0 +1,61 @@
+# diagnostics.sh — shared PostHog emitter for bash-side setup code.
+#
+# Source this file after $PROJECT_ROOT is set:
+#
+#   source "$PROJECT_ROOT/setup/lib/diagnostics.sh"
+#   ph_event bootstrap_completed status=success platform=macos
+#
+# All emits are fire-and-forget (background curl, 3s max timeout); they
+# never fail the caller. Honors NANOCLAW_NO_DIAGNOSTICS=1. The distinct_id
+# is persisted at data/install-id so the bash + node halves of setup use
+# the same id and events from one install join into a single funnel.
+
+NANOCLAW_PH_KEY='phc_fx1Hhx9ucz8GuaJC8LVZWO8u03yXZZJJ6ObS4yplnaP'
+NANOCLAW_PH_URL='https://us.i.posthog.com/capture/'
+
+# Resolve or create the persisted install id. Echoes the id (lowercase uuid).
+# Creates data/install-id on first use. Safe to call pre-Node: uses only
+# bash + uuidgen/urandom fallback + mkdir.
+ph_install_id() {
+  local root="${NANOCLAW_PROJECT_ROOT:-${PROJECT_ROOT:-$PWD}}"
+  local f="$root/data/install-id"
+  if [ ! -s "$f" ]; then
+    mkdir -p "$(dirname "$f")" 2>/dev/null || return 0
+    local id
+    id=$(uuidgen 2>/dev/null \
+      || cat /proc/sys/kernel/random/uuid 2>/dev/null \
+      || printf 'fallback-%s-%s' "$(date +%s)" "$$")
+    printf '%s' "$id" | tr 'A-Z' 'a-z' > "$f" 2>/dev/null || return 0
+  fi
+  cat "$f" 2>/dev/null
+}
+
+# Emit a PostHog event. First arg is the event name; remaining args are
+# `key=value` pairs merged into properties. Values are JSON-escaped for
+# quotes and backslashes; keep them short and alphanumeric-ish.
+ph_event() {
+  [ "${NANOCLAW_NO_DIAGNOSTICS:-}" = "1" ] && return 0
+  local event=$1
+  shift
+  local id
+  id=$(ph_install_id)
+  [ -z "$id" ] && return 0
+
+  local props='' first=1 kv k v
+  for kv in "$@"; do
+    k="${kv%%=*}"
+    v="${kv#*=}"
+    v=${v//\\/\\\\}
+    v=${v//\"/\\\"}
+    if [ "$first" = "1" ]; then first=0; else props+=','; fi
+    props+="\"$k\":\"$v\""
+  done
+
+  local payload
+  payload=$(printf '{"api_key":"%s","event":"%s","distinct_id":"%s","properties":{%s}}' \
+    "$NANOCLAW_PH_KEY" "$event" "$id" "$props")
+
+  curl -sS --max-time 3 -X POST "$NANOCLAW_PH_URL" \
+    -H 'Content-Type: application/json' \
+    -d "$payload" >/dev/null 2>&1 &
+}

setup/lib/diagnostics.ts

@@ -0,0 +1,70 @@
+/**
+ * Thin PostHog emitter shared across setup:auto code. Fire-and-forget —
+ * never throws, never blocks. Reuses data/install-id (same file bash
+ * uses in setup/lib/diagnostics.sh) so events from the bash and node
+ * halves of a single install join into one funnel.
+ *
+ * Honors NANOCLAW_NO_DIAGNOSTICS=1.
+ */
+import { randomUUID } from 'crypto';
+import fs from 'fs';
+import path from 'path';
+
+const POSTHOG_KEY = 'phc_fx1Hhx9ucz8GuaJC8LVZWO8u03yXZZJJ6ObS4yplnaP';
+const POSTHOG_URL = 'https://us.i.posthog.com/capture/';
+const INSTALL_ID_PATH = path.join('data', 'install-id');
+
+let cached: string | null = null;
+
+export function installId(): string {
+  if (cached) return cached;
+  try {
+    const existing = fs.readFileSync(INSTALL_ID_PATH, 'utf-8').trim();
+    if (existing) {
+      cached = existing;
+      return existing;
+    }
+  } catch {
+    // fall through to create
+  }
+  const id = randomUUID().toLowerCase();
+  try {
+    fs.mkdirSync(path.dirname(INSTALL_ID_PATH), { recursive: true });
+    fs.writeFileSync(INSTALL_ID_PATH, id);
+  } catch {
+    // best-effort; still return the id so the event fires
+  }
+  cached = id;
+  return id;
+}
+
+export function emit(
+  event: string,
+  props: Record<string, string | number | boolean | undefined> = {},
+): void {
+  if (process.env.NANOCLAW_NO_DIAGNOSTICS === '1') return;
+
+  const cleaned: Record<string, unknown> = { platform: process.platform };
+  for (const [k, v] of Object.entries(props)) {
+    if (v === undefined) continue;
+    cleaned[k] = v;
+  }
+
+  const body = JSON.stringify({
+    api_key: POSTHOG_KEY,
+    event,
+    distinct_id: installId(),
+    properties: cleaned,
+  });
+
+  const ctrl = new AbortController();
+  const timer = setTimeout(() => ctrl.abort(), 3000);
+  void fetch(POSTHOG_URL, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body,
+    signal: ctrl.signal,
+  })
+    .catch(() => {})
+    .finally(() => clearTimeout(timer));
+}

setup/lib/runner.ts

@@ -19,6 +19,7 @@ import k from 'kleur';
 
 import * as setupLog from '../logs.js';
 import { offerClaudeAssist } from './claude-assist.js';
+import { emit as phEmit } from './diagnostics.js';
 import { fitToWidth } from './theme.js';
 
 export type Fields = Record<string, string>;
@@ -186,11 +187,17 @@ export async function runQuietStep(
 ): Promise<StepResult & { rawLog: string; durationMs: number }> {
   const rawLog = setupLog.stepRawLog(stepName);
   const start = Date.now();
+  phEmit('step_started', { step: stepName });
   const result = await runUnderSpinner(labels, () =>
     spawnStep(stepName, extra, () => {}, rawLog),
   );
   const durationMs = Date.now() - start;
   writeStepEntry(stepName, result, durationMs, rawLog);
+  phEmit('step_completed', {
+    step: stepName,
+    status: outcomeStatus(result),
+    duration_ms: durationMs,
+  });
   return { ...result, rawLog, durationMs };
 }
 
@@ -209,6 +216,7 @@ export async function runQuietChild(
 ): Promise<QuietChildResult & { rawLog: string; durationMs: number }> {
   const rawLog = setupLog.stepRawLog(logName);
   const start = Date.now();
+  phEmit('step_started', { step: logName });
   const result = await runUnderSpinner(labels, () =>
     spawnQuiet(cmd, args, rawLog, opts?.env),
   );
@@ -223,9 +231,17 @@ export async function runQuietChild(
       ? 'skipped'
       : 'success';
   setupLog.step(logName, status, durationMs, fields, rawLog);
+  phEmit('step_completed', { step: logName, status, duration_ms: durationMs });
   return { ...result, rawLog, durationMs };
 }
 
+/** Collapse a step run into the three-way status used by diagnostics + progression log. */
+function outcomeStatus(result: StepResult): 'success' | 'skipped' | 'failed' {
+  const rawStatus = result.terminal?.fields.STATUS;
+  if (!result.ok) return 'failed';
+  return rawStatus === 'skipped' ? 'skipped' : 'success';
+}
+
 /** Turn a step's terminal-block fields into a concise progression-log entry. */
 export function writeStepEntry(
   stepName: string,
@@ -318,6 +334,7 @@ export async function fail(
   rawLogPath?: string,
 ): Promise<never> {
   setupLog.abort(stepName, msg);
+  phEmit('setup_aborted', { step: stepName, reason: msg });
   p.log.error(msg);
   if (hint) p.log.message(k.dim(hint));
   p.log.message(k.dim('Logs: logs/setup.log · Raw: logs/setup-steps/'));