feat: Add PeerTube & PieFed auto-update, improve classifier

Add auto-update scripts and review examples for PeerTube and PieFed,
bringing total auto-updating services to three.

The classifier now includes the current and target version in the
prompt so it can correctly evaluate conditional upgrade notes like
"follow v8.1.0 instructions if upgrading from <= v8.0.2". Without
this context the model would conservatively flag patch releases as
manual.

All auto-update wrappers now use `bash -euo pipefail` when calling
remote scripts so failures in upstream deploy/upgrade scripts
propagate correctly instead of silently succeeding.

test_classifier.py now accepts a service name argument and derives
realistic version numbers from the release notes for testing.

services/piefed/review-examples/auto-2.txt

@@ -0,0 +1,25 @@
+action: auto
+reason: Feature release with new functionality like private communities, pronoun flairs, and emoji improvements. No breaking changes or manual migration steps required.
+---
+ - Pronouns - when you put pronouns into Extra Fields on your profile that is used as a flair in all communities where you haven't set a flair yet
+ - Private communities - no federation, only certain roles (depends on the community) can invite new people
+ - Plain http web UI (no SSL required) with SSL used during federation - see http://retro.piefed.com. Helpful for development, extremely bad internet connections or very old computers.
+ - Mastodon can now quote-boost PieFed posts
+ - Downvotes can be turned off completely in a community, not just instance-wide
+ - Admins can sticky a post on the home page, not just mods in their communities
+ - Auto-delete of replies on remote instances when reply author has been blocked by parent content author (only works in PieFed communities due to a ActivityPub limitation)
+ - On home page when showing number of replies a post has, calculate the sum of the replies on all cross-posts and display that
+ - New users can only do 3 posts in their first 24h, to reduce floods of posts by that guy who keeps deleting his accounts and making new ones
+ - Improve emoji federation compatibility
+ - Change order of emoji in picker to present most-used ones first
+ - Optional daily time limit on usage to help people use PieFed less. Client-side tracking for privacy.
+ - A way to report posts that need to be tagged as AI generated
+ - Better accessibility
+ - Improved handling of bold and italics in markdown parsing
+ - Don't accept votes on posts from people the author has blocked
+ - Admins can resend email address verification email
+ - Admins can add notes to instances to keep track of defederation reasons, etc
+ - Search form has been simplified
+ - Option for admins to disable the em-dash detector
+ - Multiple minor bugfixes and security enhancements
+ - Translation updates for 5 languages