feat(13-02): generalize adapter contract with portals[] array

TenderSourceAdapter gains a readonly portals: readonly string[] field
so one adapter can serve multiple portals (NetServer: 3, Plan 13-04)
and so SourceRegistry can gate registration per-portal (INGEST-07).
DoeOpenDataAdapter declares portals = ['doe-opendata'] additively,
no behavior change.

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

apps/api/src/tenders/adapters/tender-source-adapter.interface.ts

@@ -15,6 +15,17 @@ import type { RawTenderRecord, SourceType } from '../tender.types';
 export interface TenderSourceAdapter {
   readonly sourceType: SourceType;
 
+  /**
+   * The source portal(s) this adapter serves (e.g. `['doe-opendata']`, or
+   * `['tender24', 'lhs-vpbw', 'vergabe.landbw']` for the config-driven
+   * NetServer adapter, Plan 13-04). `portals` decouples "one adapter" from
+   * "one portal" (INGEST-02) and is the hook `SourceRegistry.register()`
+   * checks against the AGB-prohibited denylist (INGEST-07/D-06) — every
+   * portal an adapter declares is checked, so a mixed array containing a
+   * denylisted portal alongside legitimate ones is rejected wholesale.
+   */
+  readonly portals: readonly string[];
+
   /**
    * Fetch and lightly parse all open-tender ("tender"-tagged", D-02)
    * notices for the given calendar day (Europe/Berlin), already filtered —