🎸❤️‍🩹 Allow adding auto-patch policies to (and removing from) existing installers for Fleet-maintained apps

[eugkuo]

Goal

User story
As an IT admin,
I want to patch software through Fleet
so that I can make sure host software is up-to-date to avoid vulnerabilities and offer the latest features to end users.

Key result

Auto-update (patch) any software without writing custom policies

Original requests

#21825

Context

• Design: @eugkuo
• Dev: @mostlikelee

Changes

Product

• UI changes: Figma design

  Allow adding auto-patch policies to (and removing from) existing installers for Fleet-maintained apps, as a Fleet-maintained policy. Revise copy on Add software modals. Add to Actions drop-down (potentially as first item if we haven't done 7 yet). Depends on 🎸❤️‍🩹 Software title page: Add software button + host counts on versions #28051, ❤️‍🩹 See policies on Software title page #28053, 🎸❤️‍🩹 Revise software installer scoping #28058, and 🎸❤️‍🩹 Add Fleet-maintained policy support #28059.

• CLI (fleetctl) usage changes: No changes
• YAML changes: TODO
• REST API changes: TODO add ability to edit a software title to turn on/off patching for latest version
• Fleet's agent (fleetd) changes: No changes
• GitOps mode changes: TODO
• Activity changes: TODO
• Permissions changes: No changes
• Changes to paid features or tiers: Fleet Premium
• My device and fleetdm.com/better changes: No changes
• First draft of test plan added
• Other reference documentation changes: No changes
• Once shipped, requester has been notified
• Once shipped, dogfooding issue has been filed

Engineering

• Test plan is finalized
• Contributor API changes: No changes
• Feature guide changes: At minimum changes to Automatically install software, potentially a new article
• Database schema migrations: TODO

ℹ️  Please read this issue carefully and understand it. Pay special attention to UI wireframes, especially "dev notes".

QA

Risk assessment

• Risk level: Low for regressions, med-high for implementation due to edge cases
• Risk description: TODO

Test plan

Make sure to go through the list and consider all events that might be related to this story, so we catch edge cases earlier.

1. Step 1
2. Step 2
3. Step 3

Testing notes

Confirmation

1. Engineer: Added comment to user story confirming successful completion of test plan.
2. QA: Added comment to user story confirming successful completion of test plan.

[iansltx]

Note copied from #28061: need to discuss policy behavior (auto-patch policy deletion?) when a custom package is edited (or advanced options are modified?).