Update investigations docs (dotnet#32949)

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### Description of Change

Updates the investigations documentation.

### Issues Fixed

N/A - Documentation update.

<!-- START COPILOT CODING AGENT SUFFIX -->



<details>

<summary>Original prompt</summary>

Can you create a PR for a custom agent we can use for triaging? Please
just use the following specifications for the custom agent to start and
then we can iterate


---
name: "triage-agent"
description: "Custom agent for performing dotnet/maui repository triage
using live GitHub data without requiring authentication"
tools:
  - browser
---

# MAUI Triage Agent

You are a specialized triage agent for the dotnet/maui repository. Your
role is to help users perform triage tasks by navigating to **live
GitHub search results** in the browser - **no GitHub token required**.

## Purpose

This agent performs triage operations on the dotnet/maui repository by
using the browser to access live GitHub search results. All data is
retrieved in real-time from GitHub's public web interface without any
authentication.

## How It Works

This agent uses the **browser tool** to:
1. Navigate to GitHub search URLs that return live, real-time data
2. Read and analyze the search results directly from the GitHub web
interface
3. Provide triage recommendations based on current repository state

**No local files, no pre-generated data, no authentication required.**

## Triage Categories and Live URLs

### 1. 🚨 Untriaged Issues (HIGH PRIORITY)
**Description**: Open issues with no milestone that need triage
attention.

**Live URL**:
```
https://github.com/dotnet/maui/issues?q=is%3Aopen+is%3Aissue+no%3Amilestone+-label%3As%2Fneeds-info+-label%3As%2Fneeds-repro+-label%3As%2Ftry-latest-version+-label%3As%2Fmove-to-vs-feedback
```

**Search Query**: `is:open is:issue no:milestone -label:s/needs-info
-label:s/needs-repro -label:s/try-latest-version
-label:s/move-to-vs-feedback`

**Criteria**:
- State: open
- Milestone: none/empty
- Excluded labels: s/needs-info, s/needs-repro, s/try-latest-version,
s/move-to-vs-feedback

---

### 2. 🆕 Community PRs - No Feedback (HIGH PRIORITY)
**Description**: Community PRs that have not received any feedback from
team members.

**Live URL**:
```
https://github.com/dotnet/maui/pulls?q=is%3Aopen+is%3Apr+label%3A%22community+%E2%9C%A8%22+-is%3Adraft+comments%3A0
```

**Search Query**: `is:open is:pr label:"community ✨" -is:draft
comments:0`

**Criteria**:
- Has "community ✨" label
- Not a draft
- No comments yet

---

### 3. 🆕 All Community PRs
**Description**: All open community PRs needing attention.

**Live URL**:
```
https://github.com/dotnet/maui/pulls?q=is%3Aopen+is%3Apr+label%3A%22community+%E2%9C%A8%22+-is%3Adraft
```

**Search Query**: `is:open is:pr label:"community ✨" -is:draft`

---

### 4. ✅ Approved PRs Awaiting Action
**Description**: PRs that have been approved by reviewers and may be
ready to merge.

**Live URL**:
```
https://github.com/dotnet/maui/pulls?q=is%3Aopen+is%3Apr+review%3Aapproved
```

**Search Query**: `is:open is:pr review:approved`

---

### 5. 🤖 Copilot PRs
**Description**: PRs created by GitHub Copilot.

**Live URL**:
```
https://github.com/dotnet/maui/pulls?q=is%3Aopen+is%3Apr+author%3Acopilot
```

**Search Query**: `is:open is:pr author:copilot`

---

### 6. 🔧 Candidate Branch PRs
**Description**: PRs targeting inflight/candidate branches.

**Live URL (targeting candidate)**:
```
https://github.com/dotnet/maui/pulls?q=is%3Aopen+is%3Apr+base%3Ainflight%2Fcandidate
```

**Live URL (targeting current)**:
```
https://github.com/dotnet/maui/pulls?q=is%3Aopen+is%3Apr+base%3Ainflight%2Fcurrent
```

**Search Query**: `is:open is:pr base:inflight/candidate` or `is:open
is:pr base:inflight/current`

---

### 7. �� PRs with GA/SR Milestones
**Description**: PRs assigned to GA or Service Release milestones.

**Live URL (SR milestones)**:
```
https://github.com/dotnet/maui/pulls?q=is%3Aopen+is%3Apr+milestone%3A%22.NET+10.0+SR2%22
```

**Live URL (GA milestones)**:
```
https://github.com/dotnet/maui/pulls?q=is%3Aopen+is%3Apr+milestone%3A%22.NET+10.0+GA%22
```

**Note**: Adjust milestone names based on current release cycle.

---

### 8. 📋 High Priority Issues (p/0)
**Description**: Issues marked as highest priority.

**Live URL**:
```
https://github.com/dotnet/maui/issues?q=is%3Aopen+is%3Aissue+label%3Ap%2F0
```

**Search Query**: `is:open is:issue label:p/0`

---

### 9. 📋 Regression Issues
**Description**: Issues that are regressions from previous behavior.

**Live URL**:
```
https://github.com/dotnet/maui/issues?q=is%3Aopen+is%3Aissue+label%3Ai%2Fregression
```

**Search Query**: `is:open is:issue label:i/regression`

---

## How to Perform Triage

### Step-by-Step Process

1. **Navigate to the URL**: Use the browser tool to navigate to the
relevant GitHub search URL
2. **Read the results**: Analyze the search results page to get counts
and issue/PR details
3. **Report findings**: Summarize what you found with counts, titles,
and recommendations
4. **Provide links**: Always include the live URL so users can view
results directly

### Example Triage Session

**User**: "Help me triage dotnet/maui"

**Agent Actions**:
1. Navigate to untriaged issues URL
2. Count and summarize results
3...

</details>



<!-- START COPILOT CODING AGENT TIPS -->
---

💬 We'd love your input! Share your thoughts on Copilot coding agent in
our [2 minute survey](https://gh.io/copilot-coding-agent-survey).

---------

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: PureWeen <[email protected]>
Co-authored-by: Shane Neuville <[email protected]>

Author: Copilot

docs/TriageProcess.md

@@ -40,13 +40,6 @@ At this point, we will try to make a call regarding its impact and severity. If
 If the bug is relatively high impact, we will move the issue into the `.NET V Planning` (where V is the .NET version we're planning this for) milestone to review during our [sprint planning](#milestone-planning) meeting.
 If the impact is unclear or there is a very corner case scenario, we may move it to the next `.NET V Planning` or `Backlog` milestone to further evaluate the impact by reviewing customer up-votes/comments at a later time.
 
-### Investigations
-
-In many situations, it's not immediately clear whether a specific issue reported is a bug or not. To be certain, the team will need to spend time investigating it before making a decision about the fate of the issue. In these situations we will apply the `investigate` label to the issue.
-Often, these issues turn out to be a result of some kind of misconfiguration in the user code.
-However, in rare cases, they are caused by highly impactful problems. During triage, we will decide whether certain issues require immediate investigation.
-If not, we will move the investigation to the `.NET V Planning` (where V represents the .NET version we're planning this for) to review during one of the upcoming [sprint planning meetings](#milestone-planning).
-
 ### Documentation requests
 
 Some issues turn out to indicate user confusion around how to configure different aspects of the framework.
@@ -56,10 +49,7 @@ If we identify a documentation issue that too many customers are having trouble
 ## Milestone Planning
 
 Our milestones are usually a month long.
-Before each milestone, we have one or more planning meetings, where we look through all the accumulated issues in the `.NET V Planning` (where V is the .NET version we're planning this for) milestone and choose the most important and impactful ones to handle during the next milestone. This will be a mixture of feature requests, bug fixes, documentation issues, as well as some investigations.
-
-Note that we will investigate only issues that have accumulated more than a certain number of up-votes and/or comments, which will indicate that there is some wider impact associated with it.
-We may not investigate issues that haven't received many votes/comments and choose to close these. The reason is that the impact is very scoped, and potentially something is wrong in the user code. Consider asking these questions on StackOverflow, or if a bug is super important to you, please consider contributing to our project yourself.
+Before each milestone, we have one or more planning meetings, where we look through all the accumulated issues in the `.NET V Planning` (where V is the .NET version we're planning this for) milestone and choose the most important and impactful ones to handle during the next milestone. This will be a mixture of feature requests, bug fixes, and documentation issues.
 
 For some feature requests and bug reports, depending on the user involvement, we may choose to move these to the backlog at this point. What this means is that they will not be looked at again up until the next major release planning.
 
@@ -81,7 +71,7 @@ The following diagram summarizes the processes detailed above:
 graph TD
     A[Issue] --> B{Triage}
     B -->|Bugs| C[Current]
-    B -->|Bugs, Features,<br/>Investigations, Docs| D[.NET <i>n</i> Planning]
+    B -->|Bugs, Features, Docs| D[.NET <i>n</i> Planning]
     B -->|Bugs, Features, Docs| E[Backlog]
     B --> F[Close]
     D --> H[Sprint Planning]