Add skills and instructions management to Edit Site modal

[katinthehatsite]

Related issues

• Fixes STU-1337 and STU-1453

How AI was used in this PR

Claude Code was used to implement the changes, with the developer directing the architecture and reviewing each step.

Proposed Changes

• Move Skills and Instructions tabs from the standalone AI Settings modal into the Edit Site modal (tabs: General, Debugging, Skills, Instructions)
• Add "AI Skills" and "Agent Instructions" sections to the site Settings tab with buttons that open the Edit Site modal on the correct tab
• Add a link to open global Studio Settings on the Skills tab
• Align per-site Skills and Instructions panels with the global Studio Settings UI pattern (Installed/Available sections, dropdown menus, Install all)
• Add removeAgentInstruction IPC handler to support removing instruction files (AGENTS.md, CLAUDE.md, STUDIO.md)
• Remove the AI Settings menu item from the assistant dropdown
• Delete the standalone ai-settings-modal.tsx component
• Extract shared panels into site-settings-panels.tsx

Testing Instructions

• Start the app with npm start
• Navigate to a site's Settings tab
• Verify "AI Skills" section shows a link to Studio Settings and a "Manage site skills" button
• Verify "Agent Instructions" section shows a "Manage instructions" button
• Click "Manage site skills" — Edit Site modal should open on the Skills tab
• Click "Manage instructions" — Edit Site modal should open on the Instructions tab
• In the Skills tab, verify install/remove individual skills works and the UI matches the global Studio Settings Skills tab
• In the Instructions tab, verify install/remove instruction files works with the same UI pattern
• Click the "Studio Settings" link — global settings should open on the Skills tab
• Verify the assistant dropdown menu no longer has an "AI settings" option

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[katinthehatsite]

@nightnei this is now available for review, thank you!

[wpmobilebot]

📊 Performance Test Results

Comparing f76b7e9 vs trunk

app-size

Metric	trunk	f76b7e9	Diff	Change
App Size (Mac)	1273.57 MB	1273.60 MB	+0.02 MB	⚪ 0.0%

site-editor

Metric	trunk	f76b7e9	Diff	Change
load	1927 ms	1889 ms	38 ms	⚪ 0.0%

site-startup

Metric	trunk	f76b7e9	Diff	Change
siteCreation	8174 ms	8177 ms	+3 ms	⚪ 0.0%
siteStartup	4829 ms	4824 ms	5 ms	⚪ 0.0%

---

Results are median values from multiple test runs.

Legend: 🟢 Improvement (faster) | 🔴 Regression (slower) | ⚪ No change (<50ms diff)

[nightnei]

Hm, again I have this problem when installing doesn't work 🤔 cc @sejas @epeicher
What I did:

1. npm i
2. npm start
3. And just created a new site

On Monday, I am planning to debug my environment and find the root cause, since it seems that we need to add error handling in some places and anyway it's good to know why it doesn't work for me second time.

The code LGTM, but I would ask somebody else to test it, to ensure that it works for other folks. Feel free to not wait for my approval, most likelly it's my local issue.
https://github.com/user-attachments/assets/d8f6ba16-abf4-4e82-b06b-6ae8ca366c33

[epeicher]

Hm, again I have this problem when installing doesn't work 🤔 cc @sejas @epeicher What I did:

Hi @nightnei, the latest code changes included additional error handling, for example 02d4a71, but it definitely requires some further digging. Please let us know your findings.

[sejas]

Kat, this is looking great. Let's focus in global settings first and then resolve conflicts here.

[katinthehatsite]

Kat, this is looking great. Let's focus in global settings first and then resolve conflicts here.

Sounds good to me. From what I understand, we should first merge #2880 and then refactor based on that, is that right?

[sejas]

Yes! that will be great

[sejas]

I updated this PR to follow the same design as the Global Studio Settings. Here is how is looking so far:

Site.settings.mp4

[katinthehatsite]

Thanks for making the updates @sejas ! One thing that I am wondering is if the global or individual settings should take precedence for users for existing sites? For example, if I globally remove a skill, it also gets removed from an existing site or if I globally add a skill, it gets added to existing sites but it might mess with the specific settings the users set up per site. What do you think?

[sejas]

I think it's ok that latest action overrides what's the current state. Global modifies all sites, local modifies only your that site. We could set the expectations with better descriptions. What do you think? Would you like to review the descriptions?

[katinthehatsite]

I think it's ok that latest action overrides what's the current state. Global modifies all sites, local modifies only your that site. We could set the expectations with better descriptions. What do you think? Would you like to review the descriptions?

I looked into it a bit and I think it looks fine. I was working on documentation today and wrote about it there as well so I think we are okay to merged as is.