Load server identity from install dir, not shell CWD.

Resolve PEARDOCK_HOME / binary path /opt/peardock for .env so manual
sudo -u peardock runs no longer hit EACCES on a relative home-dir .env.

test/server-paths.test.js

@@ -0,0 +1,63 @@
+import test from 'brittle'
+import path from 'path'
+import fs from 'fs'
+import os from 'os'
+import {
+  resolveServerDataDir,
+  resolveEnvFile,
+  ensureServerDataDir,
+} from '../server/core/paths.js'
+
+test('resolveServerDataDir respects PEARDOCK_HOME', (t) => {
+  const prev = process.env.PEARDOCK_HOME
+  process.env.PEARDOCK_HOME = '/opt/peardock'
+  t.is(resolveServerDataDir(), path.resolve('/opt/peardock'))
+  if (prev === undefined) delete process.env.PEARDOCK_HOME
+  else process.env.PEARDOCK_HOME = prev
+})
+
+test('resolveEnvFile joins data dir', (t) => {
+  const prevH = process.env.PEARDOCK_HOME
+  const prevE = process.env.PEARDOCK_ENV_PATH
+  delete process.env.PEARDOCK_ENV_PATH
+  process.env.PEARDOCK_HOME = '/opt/peardock'
+  t.is(resolveEnvFile(), path.join(path.resolve('/opt/peardock'), '.env'))
+  if (prevH === undefined) delete process.env.PEARDOCK_HOME
+  else process.env.PEARDOCK_HOME = prevH
+  if (prevE === undefined) delete process.env.PEARDOCK_ENV_PATH
+  else process.env.PEARDOCK_ENV_PATH = prevE
+})
+
+test('resolveEnvFile respects PEARDOCK_ENV_PATH', (t) => {
+  const prev = process.env.PEARDOCK_ENV_PATH
+  process.env.PEARDOCK_ENV_PATH = '/custom/identity.env'
+  t.is(resolveEnvFile(), path.resolve('/custom/identity.env'))
+  if (prev === undefined) delete process.env.PEARDOCK_ENV_PATH
+  else process.env.PEARDOCK_ENV_PATH = prev
+})
+
+test('ensureServerDataDir sets PEARDOCK_HOME', (t) => {
+  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'peardock-paths-'))
+  const prevH = process.env.PEARDOCK_HOME
+  const prevCwd = process.cwd()
+  try {
+    process.env.PEARDOCK_HOME = dir
+    const r = ensureServerDataDir()
+    t.is(r.dataDir, path.resolve(dir))
+    t.is(r.envFile, path.join(path.resolve(dir), '.env'))
+    t.is(process.env.PEARDOCK_HOME, path.resolve(dir))
+  } finally {
+    try {
+      process.chdir(prevCwd)
+    } catch {
+      // ignore
+    }
+    if (prevH === undefined) delete process.env.PEARDOCK_HOME
+    else process.env.PEARDOCK_HOME = prevH
+    try {
+      fs.rmSync(dir, { recursive: true, force: true })
+    } catch {
+      // ignore
+    }
+  }
+})