fix(sync-rules): CAST(real AS INTEGER) should truncate towards zero like SQLite

[sravan27]

Problem

The number→integer path of cast() uses BigInt(Math.floor(value)), which rounds towards −∞. SQLite truncates a REAL towards zero when casting to INTEGER, so the two diverge on every negative non-integer real:

expression	SQLite	sync-rules (before)
CAST(-3.7 AS INTEGER)	-3	-4
CAST(-0.9 AS INTEGER)	0	-1
CAST(-2.1 AS INTEGER)	-2	-3

Since sync-rule expressions are evaluated client-side and must agree with the source database, an integer cast over a negative real (directly or via numeric coercion) can include/exclude rows differently on the client than on the server.

Fix

Use Math.trunc instead of Math.floor. Positive reals are unaffected (floor == trunc there), and the string/bigint cast paths are unchanged. Added regression tests; verified against the system sqlite3 as ground truth.

🤖 Generated with Claude Code

[changeset-bot]

🦋 Changeset detected

Latest commit: 647e696

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

This PR includes changesets to release 17 packages

Name	Type
@powersync/service-sync-rules	Patch
@powersync/service-core	Patch
@powersync/lib-services-framework	Patch
@powersync/service-module-convex	Patch
@powersync/service-module-mongodb-storage	Patch
@powersync/service-module-mongodb	Patch
@powersync/service-module-mssql	Patch
@powersync/service-module-mysql	Patch
@powersync/service-module-postgres-storage	Patch
@powersync/service-module-postgres	Patch
@powersync/service-module-core	Patch
@powersync/service-image	Patch
test-client	Patch
@powersync/service-rsocket-router	Patch
@powersync/lib-service-mongodb	Patch
@powersync/lib-service-postgres	Patch
@powersync/service-schema	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

---

Sravan Sridhar seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[rkistner]

@sravan27 As mentioned before, we're moving towards using the node:sqlite engine, and are not fixing further compatibility differences with our JS engine. See #666.