## Description
Adds missing analytics instrumentation for the editor AI funnel so we
can measure end-to-end usage and outcome quality.
### What was added
- Captain: Editor AI menu opened
- Captain: Generation failed
- Captain: AI-assisted message sent
### Behavior covered
- Tracks AI button click + menu open from both entry points:
- top panel sparkle button
- inline editor copilot button
- Tracks generation failures (initial + follow-up stages).
- Tracks whether accepted AI content was sent as-is or edited before
send.
### Notes
- Applies to editor Captain accept/send flow
(rewrite/summarize/reply_suggestion + follow-ups).
- Does not change Copilot sidebar flow instrumentation.
## Type of change
- [x] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality not to work as expected)
- [ ] This change requires a documentation update
## How Has This Been Tested?
### Manual verification steps
<img width="1906" height="832" alt="image"
src="https://github.com/user-attachments/assets/f0ade43b-aa8d-41be-8ca2-20a091a81f60"
/>
<img width="828" height="280" alt="image"
src="https://github.com/user-attachments/assets/be76219e-fb61-4a6e-bff5-dc085b0a3cc9"
/>
<img width="415" height="147" alt="image"
src="https://github.com/user-attachments/assets/36802c5c-33a7-49ed-bf7e-f0b02d86dccc"
/>
<img width="2040" height="516" alt="image"
src="https://github.com/user-attachments/assets/74b95288-bc86-4312-a282-14211ae8f25c"
/>
1. Open a conversation with Captain tasks enabled.
2. Click AI button in top panel and inline editor.
3. Confirm analytics events fire for:
- AI menu opened
4. Run an AI action and force a failure scenario (or empty response
path) and confirm generation-failed event.
5. Accept AI output, then:
- send without changes -> editedBeforeSend: false
- edit then send -> editedBeforeSend: true
## Checklist:
- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [ ] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules