feat(python-notebook-migration, frontend): add Jupyter panel service (visibility surface and notebook-exists signal)

[zyratlo]

What changes were proposed in this PR?

Extends JupyterPanelService with the panel-visibility surface (a BehaviorSubject plus four open/close/minimize methods) and a reactive jupyterNotebookExists$ signal. This PR is the service layer only. The button that consumes it lives in the workspace top menu bar via #5273; #5265 provides the service, #5273 consumes it.

jupyter-panel.service.ts:

• Restores BehaviorSubject to the rxjs import and re-adds the NotificationService injection.
• Panel-visibility stream: private jupyterNotebookPanelVisible = new BehaviorSubject<boolean>(false) with public jupyterNotebookPanelVisible$ = this.jupyterNotebookPanelVisible.asObservable().
• Notebook-exists signal: private jupyterNotebookExists = new BehaviorSubject<boolean>(false) with public jupyterNotebookExists$. init() resets it to false on every workflow change and sets it to true in the fetchNotebookAndMapping success branch (result === 1). It stays true through minimize and resets when switching workflows. The menu button in feat(python-notebook-migration, frontend): add AI-generate-workflow modal, panel host, and LLM loading spinner #5273 binds to this to decide whether to show.
• Four if (!this.enabled) return;-gated methods:
  • openPanel(panelName: string) — flips visibility to true when panelName === "JupyterNotebookPanel" (the existing workspace panel-system convention).
  • closeJupyterNotebookPanel() — flips visibility to false, then notebookMigrationService.deleteMapping("mapping_wid_" + workflowActionService.getWorkflow().wid).
  • minimizeJupyterNotebookPanel() — flips visibility to false.
  • openJupyterNotebookPanel() — checks notebookMigrationService.hasMapping(...); warns via notificationService.warning("No Jupyter notebook associated with this workflow.") and returns if there is no cached mapping, otherwise flips visibility to true.
• init()'s subscribe handler: on every workflow change it calls closeJupyterNotebookPanel() (which also does the stale-mapping cleanup), clears the highlight index, and resets jupyterNotebookExists to false; on a successful fetch it sets jupyterNotebookExists to true, precomputes the highlight index, and auto-opens via openJupyterNotebookPanel().

No mini-map changes: the expand control moved out of the mini-map and into the top menu bar (see #5273), so mini-map.component.* is back to its main version here.

Any related issues, documentation, discussions?

Closes #5264
Parent issue #4301
Builds on #5263 (migration-tool-mapping-highlighting), merged. The consuming menu button lives in #5273 (migration-tool-modal): #5265 provides openJupyterNotebookPanel and jupyterNotebookExists$, #5273 consumes them.

How was this PR tested?

jupyter-panel.service.spec.ts adds visibility coverage (enabled-flag cases for open/close, minimize, and the warn-vs-open branch of openJupyterNotebookPanel; disabled-flag short-circuit cases per method) and a jupyterNotebookExists$ case (starts false, flips true after a successful fetch).

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

Generated-by: Claude Code (Claude Opus 4.8)

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 76.68%. Comparing base (d5b852a) to head (db9ccb0).

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #5265      +/-   ##
============================================
- Coverage     77.70%   76.68%   -1.03%     
+ Complexity     3606     3452     -154     
============================================
  Files          1161     1161              
  Lines         46034    45933     -101     
  Branches       5099     5104       +5     
============================================
- Hits          35773    35225     -548     
- Misses         8660     9174     +514     
+ Partials       1601     1534      -67     

Flag	Coverage Δ		*Carryforward flag
access-control-service	70.00% <ø> (ø)		Carriedforward from 931b0d4
agent-service	76.76% <ø> (ø)		Carriedforward from 931b0d4
amber	67.33% <ø> (-2.73%)	⬇️	Carriedforward from 931b0d4
computing-unit-managing-service	20.49% <ø> (ø)		Carriedforward from 931b0d4
config-service	66.66% <ø> (ø)		Carriedforward from 931b0d4
file-service	67.21% <ø> (ø)		Carriedforward from 931b0d4
frontend	82.64% <100.00%> (+0.06%)	⬆️
notebook-migration-service	78.94% <ø> (ø)		Carriedforward from 931b0d4
pyamber	92.14% <ø> (-0.15%)	⬇️	Carriedforward from 931b0d4
workflow-compiling-service	55.14% <ø> (ø)		Carriedforward from 931b0d4

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

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[github-actions]

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[zyratlo]

/request-review @mengw15

[mengw15]

Could you also add a screenshot of the frontend to the PR description? Thanks. Also is there a specific reason we put the button on the mini map? (for example do we want to put it on the top menu?)

[zyratlo]

Could you also add a screenshot of the frontend to the PR description? Thanks. Also is there a specific reason we put the button on the mini map? (for example do we want to put it on the top menu?)

I added a screenshot. The placement of the button doesn't have a particular reason, that was just the most logical place we thought to put it at the time. The top menu has many buttons already so we didn't want to pollute it, but I am open to this change. What do you think?

[mengw15]

Could you also add a screenshot of the frontend to the PR description? Thanks. Also is there a specific reason we put the button on the mini map? (for example do we want to put it on the top menu?)

I added a screenshot. The placement of the button doesn't have a particular reason, that was just the most logical place we thought to put it at the time. The top menu has many buttons already so we didn't want to pollute it, but I am open to this change. What do you think?

Semantically, I think placing the button on the minimap feels a bit unusual, so I would still prefer putting it in the top menu. I also think the current button icon is a little bit confusing

[zyratlo]

Could you also add a screenshot of the frontend to the PR description? Thanks. Also is there a specific reason we put the button on the mini map? (for example do we want to put it on the top menu?)

I added a screenshot. The placement of the button doesn't have a particular reason, that was just the most logical place we thought to put it at the time. The top menu has many buttons already so we didn't want to pollute it, but I am open to this change. What do you think?

Semantically, I think placing the button on the minimap feels a bit unusual, so I would still prefer putting it in the top menu. I also think the current button icon is a little bit confusing

Ok, I will make the change to move it to the top. In terms of the icon I can change it to the Jupyter logo.

[zyratlo]

I moved the button out of the mini-map and into the top menu bar next to the AI generate button, and switched the icon to the Jupyter logo.

To keep this reviewable, the button and the service it drives are now split across two PRs:

• This PR provides the service only. JupyterPanelService now exposes the panel visibility methods plus a new jupyterNotebookExists$ signal, and it no longer touches the mini-map (those files are back to their main versions).
• feat(python-notebook-migration, frontend): add AI-generate-workflow modal, panel host, and LLM loading spinner #5273 adds the menu button that consumes the service. It calls openJupyterNotebookPanel, and it only appears when the current workflow has an associated notebook, driven by jupyterNotebookExists$.

I also updated this PR's title and description to reflect the narrower scope.

[mengw15]

LGTM