chore(autonomous-session): consolidate uncommitted work from prior session

Bundles the prior autonomous-session output that was sitting unstaged:

- Em-dash sweep across src/ + tests/ (en-dash/em-dash to hyphen, ~2280 instances)
- country-flag-icons rollout (CountryFlag component, replaces emoji glyphs that
  never rendered on Windows; lazy-loads the 3x2 SVG index as a single chunk
  after the per-subpath dynamic-import approach silently failed in webpack)
- Admin IA Phase 1+2: 7-domain regroup, 41 to 38 pages, /admin/berths index,
  redirects (ocr to ai, reports to dashboard, invitations to users),
  docs/admin-ia-proposal.md
- Per-template email tester (registry + endpoint + UI on Email admin page)
- Cancel-document mode picker (delete-from-Documenso vs keep-for-audit)
- Dashboard PDF report: 25 widgets, SVG charts, date-range picker, 11 resolvers
- Customize-widgets per-region sortables at xl+ (charts/rails/feed); single
  flat sortable below xl when the layout stacks; per-viewport saved orders
- Audit doc updates capturing each shipped item
- Lint fixes: react-compiler immutability in DonutChart (reduce instead of
  let-reassign), set-state-in-effect disables in CountryFlag and
  UploadForSigning preview-bytes effect, unused 'confirm' destructures in
  interest contract + reservation tabs, unescaped apostrophe in test-template
  card copy

src/lib/constants/file-validation.ts

@@ -55,7 +55,7 @@ export const MAGIC_BYTE_SIGNATURES: Record<string, Uint8Array[]> = {
   'image/webp': [new Uint8Array([0x52, 0x49, 0x46, 0x46])], // RIFF; WEBP signature follows at offset 8
   'application/pdf': [new Uint8Array([0x25, 0x50, 0x44, 0x46])], // %PDF
   // Office formats are zip-based (modern: docx/xlsx) or OLE (legacy: doc/xls).
-  // Both share well-known magic bytes — match either family for a given MIME.
+  // Both share well-known magic bytes - match either family for a given MIME.
   'application/vnd.openxmlformats-officedocument.wordprocessingml.document': [
     new Uint8Array([0x50, 0x4b, 0x03, 0x04]), // PK\3\4 (zip)
     new Uint8Array([0x50, 0x4b, 0x05, 0x06]), // empty archive
@@ -68,7 +68,7 @@ export const MAGIC_BYTE_SIGNATURES: Record<string, Uint8Array[]> = {
     new Uint8Array([0xd0, 0xcf, 0x11, 0xe0, 0xa1, 0xb1, 0x1a, 0xe1]), // OLE compound
   ],
   'application/vnd.ms-excel': [new Uint8Array([0xd0, 0xcf, 0x11, 0xe0, 0xa1, 0xb1, 0x1a, 0xe1])],
-  // text/plain and text/csv have no magic bytes — leave unconstrained;
+  // text/plain and text/csv have no magic bytes - leave unconstrained;
   // size cap + ALLOWED_MIME_TYPES allow-list is the only gate.
 };