SQL Server: enable connections to SQL Server 2019

[kobiebotha]

Background
SQL Server 2019 supports CDC tables, so it should work, it was just a matter of not being tested.

In this PR

• After bumping the supported minimum version, initial testing showed that SQL Server 2019 LSNs could contain lowercase hex characters e.g. 0000002e:00006a18:0001
• Official MS docs show that other versions of SQL Server might return LSNs in lowercase format too, indicating that textual LSN case is not semantically meaningful (underlying value is binary). So we probably want to support this format anyway, regardless of the server version.
• The method LSN.fromString() was updated to support either lowercase or upper case LSNs, and always uppercases when returning
  • A test was added for this

Testing performed*

1. Manual testing demonstrated nominal behavior:

Screen.Recording.2026-02-07.at.8.59.22.PM.mov

2. service-module-mssql unit tests pass (both bucket storage adapters)

[changeset-bot]

🦋 Changeset detected

Latest commit: e09e413

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 12 packages

Name	Type
@powersync/service-module-mssql	Minor
@powersync/service-image	Patch
@powersync/service-core	Patch
@powersync/service-schema	Patch
@powersync/service-core-tests	Patch
@powersync/service-module-core	Patch
@powersync/service-module-mongodb-storage	Patch
@powersync/service-module-mongodb	Patch
@powersync/service-module-mysql	Patch
@powersync/service-module-postgres-storage	Patch
@powersync/service-module-postgres	Patch
test-client	Patch

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[Rentacookie]

Great that is good news that things still work on the older version. We should then also permanently enable the unit tests for 2019 in our test pipeline. Can add 2019 into the testing matrix here.

Then we also just need a changeset.