Add diff output to x-update-baseline

[Billy O'Neal (BillyONeal)]

This is a psuedo-alternative to #1980 or at least to get similar results as intended there.

I used GPT 5.5 in authoring this change.

PS C:\Dev\vcpkg-tool\src> C:\Dev\vcpkg-tool\out\build\Win-x64-Debug-WithArtifacts\vcpkg.exe x-update-baseline --dry-run --vcpkg-root C:\Dev\vcpkg 
Fetching registry information from https://github.com/microsoft/vcpkg (HEAD)...
updated registry 'https://github.com/microsoft/vcpkg': e03dc9b29710050cd1018bc5674688108658d327 -> 42e4e33e1505c9f47b58c21e0f557c1571b751ee
Updating baselines has resulted in the following version updates:

Direct dependencies:
curl: 8.20.0#1 -> 8.21.0#1

Transitive dependencies:
zlib: 1.3.2 -> 1.3.2#1

[Billy O'Neal (BillyONeal)]

This change allows the same git fetch for the baseline update to be subsequently used by the dependency planner.

[Copilot]

Pull request overview

This PR enhances the x-update-baseline command to print a dependency version “diff” for manifest mode after baselines are updated, with a new --quiet switch to suppress that output. It also refactors remote git baseline resolution to reuse the installed lockfile fetch/update mechanism, and adds an end-to-end test suite covering the new diff output.

Changes:

• Add manifest dependency version diff output (direct vs transitive) to vcpkg x-update-baseline plus --quiet to suppress it.
• Switch remote registry baseline resolution to use LockFile::get_or_fetch() / ensure_up_to_date() rather than a direct git fetch call path.
• Add PowerShell e2e coverage for the new output and quiet mode.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/vcpkg/configuration.cpp	Reworks remote registry latest-commit retrieval to go through the installed lockfile fetch/update flow.
src/vcpkg/commands.update-baseline.cpp	Implements version snapshotting + diff printing for manifest dependencies and adds --quiet; updates command signature to accept triplets.
src/vcpkg/commands.cpp	Moves x-update-baseline registration into the triplet-command tier to supply default/host triplets.
src/vcpkg/base/files.cpp	Adjusts Windows exclusive lock file handle flags and documents POSIX flock/unlink inode considerations.
locales/messages.json	Adds new messages for diff output sections and updates several existing strings used by the command.
include/vcpkg/commands.update-baseline.h	Updates the command entrypoint signature to include default/host triplets.
include/vcpkg/base/message-data.inc.h	Adds/updates message declarations used by the new output and switches.
include/vcpkg/base/contractual-constants.h	Introduces SwitchQuiet constant for the new CLI switch.
azure-pipelines/end-to-end-tests-dir/update-baseline.ps1	New e2e tests validating diff output (direct/transitive), quiet mode, and no-diff behavior.

[Billy O'Neal (BillyONeal)]

It was actually wrong for portsdiff because sometimes the user only specifies one commit there

[Victor Romero (vicroms)]

--quiet is doing a bit more than advertised (just suppressing output) by actually completely skipping the baseline comparison, but I don't feel strong enough about it to suggest making it a different option.

[Billy O'Neal (BillyONeal)]

by actually completely skipping the baseline comparison

Hmm that seems like a huge bug. Let me double check.

[Victor Romero (vicroms)]

by actually completely skipping the baseline comparison

Hmm that seems like a huge bug. Let me double check.

I think it's fine. That feature is only useful when there's output and skipping it doesn't interfere with the actual "update the baseline" part.

[Billy O'Neal (BillyONeal)]

I think it's fine. That feature is only useful when there's output and skipping it doesn't interfere with the actual "update the baseline" part.

Ohhh yeah in that case the comparison is only to print the output so it would be pointless to do without that.