ots: stop showing 'Digital Artifacts: None' for OTS commits

Two UI surfaces were showing 'None' under the Digital Artifacts label
for transactions that ARE OpenTimestamps calendar commits:

- transaction.component.html: 'None' was rendered whenever the
  parser-derived digitalArtifacts list was empty. OTS isn't
  parser-derivable (it's indexer-side knowledge), so OTS-only txs
  always landed in the empty bucket -- yet <app-ots-viewer> right
  below it rendered a full OTS panel, contradicting 'None'.
  Hide 'None' when tx.isOtsCommit === true; the OTS viewer carries
  the message.

- block-overview-tooltip.component.{ts,html}: same root cause via a
  different path. hasAnyOrdpoolFlag() in ordpool-parser explicitly
  excludes ordpool_ots, so the fetcher returned [] for OTS-only txs
  and the tooltip showed 'None'. Compute isOtsCommit from
  tx.flags & ordpool_ots (bit 81 survives the JSON Number round-trip
  because precision loss happens in the lower 29 bits, not the high
  end), suppress 'None', and render a small inline OpenTimestamps
  panel.

Author: hans-crypto

frontend/src/app/components/block-overview-tooltip/block-overview-tooltip.component.html

@@ -121,10 +121,22 @@
             Please try again!
           </ng-container>
 
-          <ng-container *ngIf="i.digitalArtifacts && !i.digitalArtifacts.length">
+          <!-- HACK -- Ordpool: hide "None" when the tx is a known OTS
+               commit -- the OTS panel below already says what's in it. -->
+          <ng-container *ngIf="i.digitalArtifacts && !i.digitalArtifacts.length && !isOtsCommit">
             None
           </ng-container>
 
+          <!-- HACK -- Ordpool: OTS commits aren't parser-derivable, so they
+               don't appear in `i.digitalArtifacts`. Render a small inline
+               summary directly from the tx.flags bit instead. -->
+          <div *ngIf="isOtsCommit" class="text-left" style="width: 300px;">
+            <strong>OpenTimestamps</strong>
+            <div class="smaller-text" style="opacity: 0.7;">
+              Calendar batch commit anchoring a Merkle root in OP_RETURN
+            </div>
+          </div>
+
           <div class="text-left" style="width: 300px;" *ngIf="i.digitalArtifacts && i.digitalArtifacts.length">
             <app-digital-artifact-viewer
               [showDetails]="false"

frontend/src/app/components/block-overview-tooltip/block-overview-tooltip.component.ts

@@ -4,7 +4,7 @@ import { Price } from '@app/services/price.service';
 import { TransactionStripped } from '@interfaces/node-api.interface.js';
 import { Filter, FilterMode, TransactionFlags, toFilters } from '@app/shared/filters.utils';
 import { Block } from '@interfaces/electrs.interface.js';
-import { DigitalArtifact, DigitalArtifactAnalyserService } from 'ordpool-parser';
+import { DigitalArtifact, DigitalArtifactAnalyserService, OrdpoolTransactionFlags } from 'ordpool-parser';
 import { Observable, catchError, of, startWith } from 'rxjs';
 import { DigitalArtifactsFetcherService } from '@app/services/ordinals/digital-artifacts-fetcher.service';
 
@@ -39,6 +39,10 @@ export class BlockOverviewTooltipComponent implements OnChanges {
   timeMode: 'mempool' | 'mined' | 'missed' | 'after' = 'mempool';
   filters: Filter[] = [];
   activeFilters: { [key: string]: boolean } = {};
+  // HACK -- Ordpool: surfaced separately so the Digital Artifacts cell
+  // can render an OTS line and suppress the misleading "None" message
+  // (OTS isn't parser-derivable; the parser-based fetcher returns []).
+  isOtsCommit: boolean = false;
 
   tooltipPosition: Position = { x: 0, y: 0 };
 
@@ -74,6 +78,9 @@ export class BlockOverviewTooltipComponent implements OnChanges {
       this.feeRate = this.fee / this.vsize;
       this.effectiveRate = this.tx.rate;
       const txFlags = BigInt(this.tx.flags) || 0n;
+      // HACK -- Ordpool: bit 81 is preserved across the JSON Number
+      // round-trip even though the lower bits get quantized to ~2^29.
+      this.isOtsCommit = (txFlags & OrdpoolTransactionFlags.ordpool_ots) !== 0n;
       this.acceleration = this.tx.acc || (txFlags & TransactionFlags.acceleration);
       this.hasEffectiveRate = this.tx.acc || !(Math.abs((this.fee / this.vsize) - this.effectiveRate) <= 0.1 && Math.abs((this.fee / Math.ceil(this.vsize)) - this.effectiveRate) <= 0.1)
         || (txFlags && (txFlags & (TransactionFlags.cpfp_child | TransactionFlags.cpfp_parent)) > 0n);

frontend/src/app/components/transaction/transaction.component.html

@@ -149,7 +149,10 @@ <h2>Digital Artifacts</h2>
 
       <div class="box">
 
-        <ng-container *ngIf="!digitalArtifacts.length">
+        <!-- HACK -- Ordpool: don't show "None" when the tx is a known
+             OpenTimestamps commit -- <app-ots-viewer> below renders its
+             own panel for those, so "None" would directly contradict it. -->
+        <ng-container *ngIf="!digitalArtifacts.length && tx.isOtsCommit !== true">
           None
         </ng-container>