refactor(frontend): remove two pieces of unreachable code

[Raja-Hamid]

What changes were proposed in this PR?

Removes two pieces of unreachable code, each surfaced by a surviving mutation — i.e. each was demonstrated to have no observable effect, not merely suspected. No user-facing behavior changes, hence refactor.

1. hugging-face-image-upload.component.html — an unreachable fallback

-<span>{{ displayFileName || "Selected image" }}</span>
+<span>{{ displayFileName }}</span>

The enclosing block is *ngIf="previewSrc", and previewSrc returns this.hasImage ? this.formControl.value : "" — so it is non-empty exactly when hasImage is true. displayFileName returns fileName or, failing that, "Uploaded image" whenever hasImage is true. It is therefore never empty where this renders, and the right-hand side of the || can never be evaluated.

2. drag-drop.service.ts — a guard subsumed by the next one

 const jointLink = paper.getModelById(link.linkID) as joint.dia.Link;
-if (!jointLink) {
-  continue;
-}
-
 const linkView = paper.findViewByModel(jointLink) as joint.dia.LinkView;
 if (!linkView) {
   continue;
 }

findViewByModel in jointjs 3.5.4 resolves its argument with (isString(cell) || isNumber(cell)) ? cell : (cell && cell.id) and returns this._views[id]. The cell && cell.id short-circuits on undefined, so the call returns undefined rather than throwing, and the !linkView guard already catches everything !jointLink did.

Worth noting for reviewers: this guard was not meaningless. findIntersectedLink iterates the Texera graph but resolves each link against the JointJS paper, and those two can genuinely diverge, so getModelById really can return undefined at runtime. That path is still handled, just one guard later. (The as joint.dia.Link cast is what hides the undefined case from the type checker.)

No screenshots: neither change alters rendered output or behavior, that is precisely the claim under test.

Any related issues, documentation, discussions?

Closes #7459

How was this PR tested?

Because this is a refactor with no behavior change, the removed branches cannot be driven red by definition. Instead, two regression guards were added that pass both before and after the removals, pinning the behavior the removals must preserve:

- hugging-face-image-upload.component.spec.ts, an image with no filename renders exactly Uploaded image; a known filename renders instead; and with no image the preview block does not render at all, so the label is never empty.
- drag-drop.service.spec.ts, a link present in the Texera graph but with no model in the JointJS paper is skipped: findIntersectedLink returns null and does not throw. (Removing both guards makes this fail on linkView.el, so it genuinely pins the path.)

corepack yarn ng test --watch=false \
  --include="**/hugging-face-image-upload.component.spec.ts" \
  --include="**/drag-drop.service.spec.ts"

- Against unmodified source: 2 files, 56/56 passing — the new guards are green before any code is touched.
- After both removals: 2 files, 56/56 passing, with no assertion edits.

Wider sweep, adding the specs for the formly config that registers the component:

corepack yarn ng test --watch=false \
  --include="**/formly*.spec.ts" \
  --include="**/hugging-face-image-upload.component.spec.ts" \
  --include="**/drag-drop.service.spec.ts"
→ 4 files, 83/83 passing

yarn prettier-eslint reports all four touched files unchanged.

Was this PR authored or co-authored using generative AI tooling?

Generated-by: Yes alongside Claude Code.

[github-actions]

👋 Thanks for opening this pull request, @Raja-Hamid!

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[github-actions]

Automated Reviewer Suggestions

Based on the git blame history of the changed files, we recommend the following reviewers:

• Contributors with relevant context: @PG1204, @mengw15, @aglinxinyuan
  You can notify them by mentioning @PG1204, @mengw15, @aglinxinyuan in a comment.

[Raja-Hamid]

Hey @aglinxinyuan, Need your review on this.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.40%. Comparing base (42d08a3) to head (8e13591).

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #7512      +/-   ##
============================================
+ Coverage     86.38%   86.40%   +0.01%     
  Complexity     4211     4211              
============================================
  Files          1169     1169              
  Lines         46750    46748       -2     
  Branches       5203     5201       -2     
============================================
+ Hits          40387    40391       +4     
+ Misses         4641     4635       -6     
  Partials       1722     1722              

Flag	Coverage Δ		*Carryforward flag
access-control-service	70.00% <ø> (ø)		Carriedforward from 42d08a3
agent-service	86.87% <ø> (ø)		Carriedforward from 42d08a3
amber	81.87% <ø> (ø)		Carriedforward from 42d08a3
computing-unit-managing-service	50.72% <ø> (ø)		Carriedforward from 42d08a3
config-service	65.97% <ø> (ø)		Carriedforward from 42d08a3
file-service	69.05% <ø> (ø)		Carriedforward from 42d08a3
frontend	89.26% <100.00%> (+0.02%)	⬆️
notebook-migration-service	78.89% <ø> (ø)		Carriedforward from 42d08a3
pyamber	97.56% <ø> (ø)		Carriedforward from 42d08a3
workflow-compiling-service	26.31% <ø> (ø)		Carriedforward from 42d08a3

*This pull request uses carry forward flags. Click here to find out more.

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[aglinxinyuan]

👋 Thanks for opening this pull request, @Raja-Hamid!

It looks like the pull request description doesn't quite follow our template yet:

• The How was this PR tested? section is missing; please keep the template's headings.
• The Was this PR authored or co-authored using generative AI tooling? section is missing; please keep the template's headings.

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@Raja-Hamid please address this comment.