fix: bump immutable override to clear high-severity audit

[HarshMN2345]

Summary

• bun audit --audit-level high was failing CI on two high-severity immutable advisories (pulled in transitively via sass): a 32-bit trie overflow DoS and a hash-collision algorithmic complexity DoS.
• Bumped the existing immutable override from ^5.1.5 to ^5.1.8 to reach the patched range.
• No direct dependency changes — only the transitive override.

Test plan

• bun audit --audit-level high — 0 vulnerabilities
• bun install --frozen-lockfile — succeeds
• bun run check — 0 errors

[appwrite]

Console (appwrite/console)

Project ID: 688b7bf400350cbd60e9

Sites (1)

Site	Status	Logs	Preview	QR
console-stage 688b7cf6003b1842c9dc	Processing	View Logs	Preview URL

Tip

Schedule functions to run as often as every minute with cron expressions

[greptile-apps]

Greptile Summary

This PR updates the transitive Immutable.js override to a patched release range. The main changes are:

• Raises the immutable override from ^5.1.5 to ^5.1.8.
• Resolves immutable to version 5.1.9 in the Bun lockfile.
• Updates the lockfile integrity hash for the new package.

Confidence Score: 5/5

This looks safe to merge.

• No blocking issues found in the changed code.
• The manifest and lockfile use matching override ranges.
• Immutable.js 5.1.9 satisfies Sass's declared ^5.1.5 dependency range.

Important Files Changed

Filename	Overview
package.json	Raises the existing immutable override to the patched ^5.1.8 range.
bun.lock	Synchronizes the override and resolves immutable to version 5.1.9 with its updated integrity hash.

_{Reviews (1): Last reviewed commit: "fix: bump immutable override to clear hi..." | Re-trigger Greptile}

[HarshMN2345]

Folding this into #3136 instead of a separate PR.