Apply code-review fixes: identity/pagination, load races, TLS pin, leaks

Addresses a multi-agent code review (26 confirmed findings + a URLSession
leak) across correctness, concurrency, security, and cleanup:

- MongoDocument.id: deterministic fallback (was UUID() on every access) to stop
  SwiftUI List/ForEach identity churn; getAll pagination drives its cursor off
  the real _id via documentId, so a missing _id stops paging instead of looping
  on a fabricated cursor.
- View models: per-load generation guard (+ captured-tab guard on ONU detail)
  so a cancelled or overlapping load can't commit stale results or land data on
  the wrong tab.
- JSONValue.intValue: guard Int(d) against NaN/inf/out-of-range (crash).
- ServerTrustEvaluator: hash the real SubjectPublicKeyInfo (prepend the
  algorithm-specific ASN.1 SPKI header) so a standard openssl-captured
  public-key pin actually matches; unknown key types fail closed.
- AppEnvironment.configure: clear stale cookies + Keychain creds on host change.
- FirmwareFile.isCompatible: empty metadata no longer passes as compatible-for-all.
- APIClient: invalidate URLSession on deinit (per-configure/probe leak).
- Dashboard best-effort sections keep last-good on transient failure; unified
  optical thresholds; LoginView prefill-once; populatedBuckets unique ForEach id;
  Format rounding rollover; dead-code/docstring/dedup cleanups.

Verification pending on the Mac (no Swift toolchain on the Linux dev box).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

ONUListViewModel.swift

@@ -12,6 +12,8 @@ final class ONUListViewModel {
     let stateFilter: ONULifecycleState?
 
     private let connection: MCMSConnection
+    /// Bumped per load so an overlapping/stale fetch can't commit over a newer one.
+    private var loadGeneration = 0
     init(connection: MCMSConnection, stateFilter: ONULifecycleState? = nil) {
         self.connection = connection
         self.stateFilter = stateFilter
@@ -32,13 +34,15 @@ final class ONUListViewModel {
     }
 
     func load() async {
+        loadGeneration += 1
+        let gen = loadGeneration
         phase = .loading
         do {
             let fetched = try await connection.onu.allStates()
             // Registration lives on OLT-STATE, operator names on ONU-CFG. Both best-effort.
             let registration = (try? await connection.olt.registrationMap()) ?? [:]
             let names = (try? await connection.onu.nameMap()) ?? [:]
-            onus = fetched
+            let merged = fetched
                 .map { onu in
                     var onu = onu
                     onu.resolvedLifecycle = registration[onu.id]
@@ -46,8 +50,11 @@ final class ONUListViewModel {
                     return onu
                 }
                 .sorted { $0.displayName.localizedCaseInsensitiveCompare($1.displayName) == .orderedAscending }
+            guard gen == loadGeneration, !Task.isCancelled else { return }
+            onus = merged
             phase = .loaded
         } catch {
+            guard gen == loadGeneration, !Task.isCancelled else { return }
             phase = .failed((error as? APIError)?.localizedDescription ?? error.localizedDescription)
         }
     }