docs(1099): document Payee1099s/Form1099Boxes schema and seed Form1099 permissions

- DB_SCHEMA.md §8: add Form1099Box catalog table, Payee1099 recipient master
  (with TIN at-rest encryption note), and new FK columns on Expenses /
  ExpenseSubCategories / ExpenseCategoryGroups; update TOC and Seed Data section
- DbSeeder.cs: grant Modules.Form1099 to finance (R/W/D), pastor (R), and
  board_member (R), mirroring the Form990Report + Disbursements pattern;
  idempotent (only inserts if row absent, never clobbers admin edits)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

API/ROLAC.API/Data/DbSeeder.cs

@@ -207,6 +207,11 @@ public static class DbSeeder
         ("finance", Modules.ChurchProfile,     true, true,  false, false),
         ("finance", Modules.Disbursements,     true, true,  true,  true),
         ("finance", Modules.Form990Report,     true, false, false, false),
+        // Form1099 — finance manages recipients and tracks filings; pastor and board_member
+        // get read-only oversight (same pattern as Form990Report). No Approve semantics.
+        ("finance",      Modules.Form1099, true, true,  true,  false),
+        ("pastor",       Modules.Form1099, true, false, false, false),
+        ("board_member", Modules.Form1099, true, false, false, false),
 
         // Logs — read-only. System logs are technical (pastor only); audit logs have
         // governance value, so finance and board members can read them too.