fix(UI)): ensure terminal theme application via xterm theme setter

[jhaumont]

When you try to set a theme on a widget:

"test": {
    "icon": "dharmachakra",
    "label": "test",
    "color": "#326ce5",
    "blockdef": {
      "meta": {
        "view": "term",
        "controller": "cmd",
        "cmd": "wsl.exe -d Debian --shell-type login bash -ic \"k9s\"",
        "cmd:interactive": true,
        "cmd:runonstart": true,
        "term:theme": "Dracula"
      }
    }

It's not take in account. You have to manually change the theme of the block.

Purpose of this PR is to fix this and having the widget taking into account the theme from start.

[coderabbitai]

Walkthrough

These changes refactor how the terminal theme is applied in the terminal view. A new setTheme() method is introduced in the TermWrap class that applies the theme using either the setOption() API (when available) or direct property assignment as a fallback. The TermThemeUpdater hook's useEffect is updated to call this new method instead of directly mutating the terminal options object.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Description check	❓ Inconclusive	No description was provided by the author, making it impossible to evaluate whether the description relates to the changeset.	Add a pull request description explaining the fix, the problem it addresses, and any testing performed.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main change: fixing terminal theme application by using xterm's theme setter method instead of direct mutation.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[jhaumont]

@coderabbitai review

[coderabbitai]

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[coderabbitai]

🧹 Nitpick comments (1)

frontend/app/view/term/termwrap.ts (1)

339-345: ⚡ Quick win

setOption is dead code for @xterm/xterm ^6.0.0 — simplify to direct assignment.

setOption and getOption were fully removed in xterm.js 5.0.0 in favour of terminal.options.* assignment. Since this project constrains to @xterm/xterm ^6.0.0, typeof (this.terminal as any).setOption will always evaluate to "undefined", making that branch permanently dead code. The (this.terminal as any) cast also bypasses TypeScript safety for a method that doesn't exist.

The fallback (this.terminal.options.theme = theme) is the only path ever executed, so setTheme can be simplified to match the existing sibling methods setCursorStyle and setCursorBlink, which already use direct options assignment without any guard:

♻️ Proposed refactor

     setTheme(theme: TermTypes.ITerminalOptions["theme"]) {
-        if (typeof (this.terminal as any).setOption === "function") {
-            (this.terminal as any).setOption("theme", theme);
-        } else {
-            this.terminal.options.theme = theme;
-        }
+        this.terminal.options.theme = theme;
     }

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@frontend/app/view/term/termwrap.ts` around lines 339 - 345, The setTheme
method contains dead code checking for a non-existent setOption and uses an
unnecessary any cast; simplify it to directly assign the theme to the terminal
options like the sibling methods do: remove the typeof check and (this.terminal
as any) cast, and update setTheme to set this.terminal.options.theme = theme
using the existing ITerminalOptions typing for terminal (reference: setTheme
method and terminal.options.theme).

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Nitpick comments:
In `@frontend/app/view/term/termwrap.ts`:
- Around line 339-345: The setTheme method contains dead code checking for a
non-existent setOption and uses an unnecessary any cast; simplify it to directly
assign the theme to the terminal options like the sibling methods do: remove the
typeof check and (this.terminal as any) cast, and update setTheme to set
this.terminal.options.theme = theme using the existing ITerminalOptions typing
for terminal (reference: setTheme method and terminal.options.theme).

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 83a43cc9-da8c-4bc9-846c-9246233b282d

📥 Commits

Reviewing files that changed from the base of the PR and between 2e25ea1 and 769b541.

📒 Files selected for processing (2)

• frontend/app/view/term/termtheme.ts
• frontend/app/view/term/termwrap.ts