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>

AuthModels.swift

@@ -16,8 +16,6 @@ struct AuthResponse: Decodable, EmptyRepresentable {
     private init(raw: JSONValue) { self.raw = raw }
 
     static var emptyValue: AuthResponse { AuthResponse(raw: .null) }
-
-    var email: String? { raw["email"]?.stringValue ?? raw["User"]?["email"]?.stringValue }
 }
 
 /// `GET /v{n}/ponmgr/version/` — attribute set describing the install.