feat(eoi): align prerequisites with EOI document structure

Match the gate to the actual EOI's structure (Section 2 vs Section 3) so
the rep can generate the document the moment they have what they need —
and not before.

  Required (Section 2 — top paragraph):
    - Client name
    - Client primary email
    - Client primary address

  Optional (Section 3 — left blank when absent):
    - Linked yacht (name, dimensions)
    - Linked berth (mooring number)

Previously the dialog blocked generation unless yacht AND berth were both
linked, which was overzealous — early-stage EOIs are routinely sent before
a specific berth is pinned down.

  - eoi-context.ts: yacht and berth are now nullable in the returned
    context. The hard ValidationError is now driven by the EOI's Section
    2 fields (name/email/address) rather than yacht/berth presence. The
    owner block falls back to the interest's client when no yacht is
    linked, so signing parties remain resolvable.

  - documenso-payload.ts + fill-eoi-form.ts: Section 3 form values
    render as empty strings when yacht or berth are absent, so the
    rendered PDF leaves those template inputs blank.

  - document-templates.ts: yacht.* and berth.* tokens fall back to
    empty strings; the legacy-fallback catch handler also recognises
    the new "missing required client details" error.

  - interests.service.ts: getInterestById now also returns
    `clientPrimaryEmail` and `clientHasAddress` so the Documents tab
    can compute the EOI prerequisites checklist client-side without an
    extra fetch.

  - eoi-generate-dialog.tsx: prereqs split into two groups visually —
    Required (with red ✗ when missing) and Optional (with grey – when
    absent). The Generate button only requires the Required block to
    pass. A small amber banner surfaces when Required is incomplete so
    the rep knows where to add the missing data.

Tests: 835/835 pass. Replaces the obsolete "throws on missing yacht/
berth" tests with parity coverage for the new behaviour ("builds a
valid context when yacht/berth missing", "throws when client email/
address missing"). Adds a payload test for the empty-Section-3 case.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/interests/interest-documents-tab.tsx

@@ -18,6 +18,9 @@ interface InterestData {
   yachtId?: string | null;
   berthId?: string | null;
   clientName?: string | null;
+  /** Surfaced by getInterestById for the EOI prerequisites checklist. */
+  clientPrimaryEmail?: string | null;
+  clientHasAddress?: boolean;
 }
 
 export function InterestDocumentsTab({ interestId }: InterestDocumentsTabProps) {
@@ -33,7 +36,11 @@ export function InterestDocumentsTab({ interestId }: InterestDocumentsTabProps)
   });
 
   const prerequisites = {
+    // Required (EOI Section 2 — top paragraph): name, address, email.
     hasName: Boolean(interest?.clientName),
+    hasEmail: Boolean(interest?.clientPrimaryEmail),
+    hasAddress: Boolean(interest?.clientHasAddress),
+    // Optional (EOI Section 3): yacht + berth. Render blank when absent.
     hasYacht: Boolean(interest?.yachtId),
     hasBerth: Boolean(interest?.berthId),
   };