fix(crossseed): replay strict search decision when info.name adds a bracketed title prefix (#2997)

Description

When a Search Cross-Seeds apply sends a torrent whose info.name starts with a bracketed alternate title (for example [港灯].Harbor.Lights.2022.S01.Complete.1080p.WEB-DL.HEVC.DDP5.1-GRP) and the tracker listing title omits it, rls parses the prefix as the site tag. findCandidates then gets site mismatch against the local torrent, and the strict search decision has no case in the !releasesMatch switch, so the candidate is dropped and the apply returns no_match.

This adds one case for a strict search decision with site mismatch. It replays the decision only when:

• the listing title is still metadata-consistent with the target (searchCandidateMetadataConsistent, the same check the other search fallbacks use), and
• the target matches the candidate once its site tag is cleared (releasesMatchWithReasonAndNamesAndTitles on a copy).

Group, size and file checks run as before. A plain apply with no search decision is unchanged.

No docs change: this restores the documented behavior of applying a strict search result, and adds no option.

Fixes #2997

Breaking change

No breaking change.

Behaviour change

A strict Search Cross-Seeds result whose torrent name adds a bracketed title prefix is now added instead of returning no_match. Applies without a strict search decision behave as before.

How has this been tested?

New test TestCrossSeedStrictSearchDecisionIgnoresBracketTitlePrefix in apply_file_derived_target_test.go, through Service.CrossSeed with an incoming torrent whose name and files carry the prefix and a local torrent without it:

• strict search decision: added
• no search decision: no_match
• local torrent from another group: no_match
• different file sizes: rejected
• listing title for another season: no_match

I checked that the test bites: removing the new case fails the first row, and removing the metadata check fails the last row.

go test -count=1 ./internal/services/crossseed/..., golangci-lint run on the package (0 issues), go fix -diff (clean), gofmt and go build ./... pass.

Field test: I could not run this live. It needs a tracker that lists a release without the bracketed title while its torrent carries it, and I have no such account. The CrossSeed test above, with a real metainfo built from the constructed name, is the closest check.

Performance

The new code runs only for a strict search decision that already failed with site mismatch, once per such candidate: one listing parse and one extra release match. The normal apply path and all other mismatch reasons do no new work, so I did not benchmark it.

Checklist

• My PR title follows the Conventional Commits format (it becomes the squashed commit message)
• If this changes the database schema, I have added migrations for both SQLite and PostgreSQL
• I completed the mandatory performance checks and recorded the outcome in Performance

AI disclosure

Yes. Claude Code (Claude Opus) wrote the code and the test from the issue brief. DeepSeek reviewed the diff. I checked that the test fails without the fix and ran the checks above.