Client-stepper: pre-fill existing KYC/address proofs in edit, fix identifier saves

Edit-mode now shows the previously selected KYC document type + uploaded file thumbnail
(loads from /clients/{id}/identifiers + /client_identifiers/{id}/documents). Same for
address proof on the India address step. Closes the gap where editing a client showed
an empty file picker even when proof had been uploaded on create.

Identifier-save hardened across all three callsites (create-client, edit-client,
identities-tab.createIdentifierWithDocs) - the KYC chip picker proofId is a CODE
string ('AADHAAR'), but backend ClientIdentifierRequest.documentTypeId is Long, which
Spring rejects with HttpMessageNotReadableException -> 400. resolveDocumentTypeId
helper looks up the code against /kyc/proof-types?type=id and substitutes the numeric
CodeValue id before posting. Skips silently for constitution-specific non-individual
docs that have no CodeValue mapping.

KYC payload normalises panNumber / enterprisePan / gstinNumber / cinNumber via
toUpperCase + whitespace strip so user-typed lowercase or trailing spaces don't trip
the backend regex (validation.msg.CLIENTKYC.panNumber.does.not.match.regexp).

State name match in client-address save now normalises both sides (lowercase, collapse
underscores + spaces) so legacy MADHYA_PRADESH resolves to 'Madhya Pradesh' returned
by api.postalpincode.in. Backed by tenant migration 0297.

Identities-tab resolver flattened - was returning identifiers before the per-row
forkJoin(getClientIdentificationDocuments) completed, so the view rendered empty
documents arrays. Now uses switchMap + forkJoin so the resolver awaits completion.

Also bundles concurrent work-in-progress on letter-mgmt, organization, users,
bank-calendar, shell, nominee/notes/identifier dialogs, and theming.

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

src/app/clients/edit-client/edit-client.component.html

@@ -207,7 +207,15 @@
         </button>
       }
       @if (selectedTabIndex < totalTabs - 1) {
-        <button mat-raised-button color="primary" (click)="onNext()" [disabled]="savingClient">
+        <button
+          mat-raised-button
+          color="primary"
+          (click)="onNext()"
+          [disabled]="!currentStepValid"
+          [matTooltip]="currentStepBlockerMessage"
+          [matTooltipDisabled]="currentStepValid"
+          matTooltipPosition="above"
+        >
           @if (savingClient) {
             <mat-progress-spinner diameter="18" mode="indeterminate" class="m-r-10"></mat-progress-spinner>
             Saving...