Stabilize multi-peer UI and fix container start API body

Keep the containers table scoped to the active peer with a merge store,
restore the last active server on boot with a restoring screen, start
containers without a Docker API body (v1.24+), and stop ⋮ menus from
sticking to the viewport bottom after refreshes.

client/manager.js

@@ -10,6 +10,7 @@ import {
   savePeers,
   listSavedPeers,
   getPeersCachePath,
+  setLastActivePeerId,
 } from './peerCache.js'
 import { normalizeRpcError, isBackgroundMethod } from './errors.js'
 
@@ -72,10 +73,12 @@ export class ConnectionManager extends EventEmitter {
       this._reconnect.set(id, entry)
     }
 
+    const shouldActivate = meta.setActive !== false
+
     if (this.connections.has(id)) {
       const existing = this.connections.get(id)
       if (existing.connected) {
-        this.setActive(id)
+        if (shouldActivate) this.setActive(id)
         return existing
       }
       await existing.close().catch(() => {})
@@ -109,7 +112,8 @@ export class ConnectionManager extends EventEmitter {
     }
     this.connections.set(id, conn)
     this.persist()
-    this.setActive(id)
+    // Boot restore dials all peers with setActive:false so last-known wins later
+    if (shouldActivate) this.setActive(id)
     this._ensureHealthLoop()
     this.emit('connect', conn)
     return conn
@@ -122,6 +126,11 @@ export class ConnectionManager extends EventEmitter {
     const conn = this.connections.get(id)
     if (!conn) return
     this.active = conn
+    try {
+      setLastActivePeerId(id)
+    } catch {
+      // ignore persist failures
+    }
     this.emit('active', conn)
   }
 

client/peerCache.js

@@ -15,6 +15,8 @@ import os from 'os'
 export const PEERS_CACHE_VERSION = 1
 export const LOCALSTORAGE_KEY = 'peardock_connections'
 export const LOCALSTORAGE_FLAG = 'peardock_use_localstorage'
+/** Last UI-selected active peer id (12-char prefix) */
+export const ACTIVE_PEER_KEY = 'peardock_active_peer_id'
 
 /**
  * Absolute path to the peers cache file.
@@ -99,7 +101,7 @@ export function parsePeersPayload(raw) {
   const out = {}
   for (const [key, value] of Object.entries(source)) {
     // Skip meta keys if someone stored a flat object with version
-    if (key === 'version' || key === 'updatedAt' || key === 'peers') continue
+    if (key === 'version' || key === 'updatedAt' || key === 'peers' || key === 'activePeerId') continue
     const entry = normalizePeerEntry(value, key)
     if (!entry) continue
     out[entry.id] = {
@@ -114,8 +116,9 @@ export function parsePeersPayload(raw) {
 /**
  * Build on-disk payload.
  * @param {Record<string, { publicKeyHex?: string, topicHex?: string, alias?: string|null, inviteToken?: string|null }>} peersMap
+ * @param {{ activePeerId?: string|null }} [opts]
  */
-export function buildPeersPayload(peersMap) {
+export function buildPeersPayload(peersMap, opts = {}) {
   const peers = {}
   for (const [id, value] of Object.entries(peersMap || {})) {
     const entry = normalizePeerEntry(value, id)
@@ -126,11 +129,79 @@ export function buildPeersPayload(peersMap) {
       inviteToken: entry.inviteToken,
     }
   }
-  return {
+  const payload = {
     version: PEERS_CACHE_VERSION,
     updatedAt: new Date().toISOString(),
     peers,
   }
+  if (Object.prototype.hasOwnProperty.call(opts, 'activePeerId')) {
+    if (opts.activePeerId != null && opts.activePeerId !== '') {
+      payload.activePeerId = String(opts.activePeerId).slice(0, 12)
+    }
+    // null/'' → omit (clear)
+  } else {
+    // preserve existing disk active id when not provided
+    const existing = readActivePeerIdFromFile()
+    if (existing) payload.activePeerId = existing
+  }
+  return payload
+}
+
+/**
+ * @returns {string|null}
+ */
+function readActivePeerIdFromFile() {
+  const file = getPeersCachePath()
+  try {
+    if (!fs.existsSync(file)) return null
+    const raw = JSON.parse(fs.readFileSync(file, 'utf8'))
+    const id = raw?.activePeerId
+    return id ? String(id).slice(0, 12) : null
+  } catch {
+    return null
+  }
+}
+
+/**
+ * Last known active peer id (file first, then localStorage).
+ * @returns {string|null}
+ */
+export function getLastActivePeerId() {
+  const fromFile = readActivePeerIdFromFile()
+  if (fromFile) return fromFile
+  try {
+    if (typeof localStorage !== 'undefined') {
+      const id = localStorage.getItem(ACTIVE_PEER_KEY)
+      return id ? String(id).slice(0, 12) : null
+    }
+  } catch {
+    // ignore
+  }
+  return null
+}
+
+/**
+ * Persist last active peer id (localStorage + peers.json meta when possible).
+ * @param {string|null} id
+ */
+export function setLastActivePeerId(id) {
+  const next = id ? String(id).slice(0, 12) : null
+  try {
+    if (typeof localStorage !== 'undefined') {
+      if (next) localStorage.setItem(ACTIVE_PEER_KEY, next)
+      else localStorage.removeItem(ACTIVE_PEER_KEY)
+    }
+  } catch {
+    // ignore
+  }
+  // Merge into peers.json without rewriting peer entries
+  try {
+    const peers = loadPeers()
+    if (Object.keys(peers).length === 0 && !next) return
+    writePeersToFile(peers, { activePeerId: next })
+  } catch {
+    // ignore
+  }
 }
 
 function ensureCacheDir() {
@@ -158,11 +229,12 @@ export function readPeersFromFile() {
 /**
  * Write peers to ~/.config/peardock/cache/peers.json (atomic replace).
  * @param {Record<string, object>} peersMap
+ * @param {{ activePeerId?: string|null }} [opts]
  * @returns {boolean}
  */
-export function writePeersToFile(peersMap) {
+export function writePeersToFile(peersMap, opts = {}) {
   const file = getPeersCachePath()
-  const payload = buildPeersPayload(peersMap)
+  const payload = buildPeersPayload(peersMap, opts)
   const json = JSON.stringify(payload, null, 2)
   try {
     ensureCacheDir()
@@ -231,11 +303,16 @@ export function loadPeers() {
 /**
  * Persist peers to file (+ mirror localStorage as secondary cache).
  * @param {Record<string, object>} peersMap
+ * @param {{ activePeerId?: string|null }} [opts]
  * @returns {{ ok: boolean, path: string, count: number }}
  */
-export function savePeers(peersMap) {
-  const payload = buildPeersPayload(peersMap)
-  const ok = writePeersToFile(payload.peers)
+export function savePeers(peersMap, opts = {}) {
+  const payload = buildPeersPayload(peersMap, opts)
+  // Pass through only when caller set activePeerId; otherwise preserve on disk
+  const writeOpts = Object.prototype.hasOwnProperty.call(opts, 'activePeerId')
+    ? { activePeerId: opts.activePeerId }
+    : {}
+  const ok = writePeersToFile(payload.peers, writeOpts)
 
   // Mirror for quick in-session reads / legacy code paths
   try {
@@ -243,6 +320,9 @@ export function savePeers(peersMap) {
       // Keep flat map for older readers
       localStorage.setItem(LOCALSTORAGE_KEY, JSON.stringify(payload.peers))
       localStorage.setItem(LOCALSTORAGE_FLAG, '1')
+      if (payload.activePeerId) {
+        localStorage.setItem(ACTIVE_PEER_KEY, payload.activePeerId)
+      }
     }
   } catch {
     // ignore
@@ -296,4 +376,6 @@ export default {
   normalizePeerEntry,
   readPeersFromFile,
   writePeersToFile,
+  getLastActivePeerId,
+  setLastActivePeerId,
 }