fix: pass region string directly in updateLaunchConfig.mjs instead of broken enum lookup

[cs-raj]

Problem

updateLaunchConfig.mjs was using a TypeScript enum reverse-lookup to
resolve the region value:

region: Region[process.env.NEXT_PUBLIC_CONTENTSTACK_REGION]

The Region enum in @contentstack/delivery-sdk only has three keys:
EU, AZURE_EU, GCP_EU. Any other value — NA, azure-na, gcp-na, or even
lowercase eu — resolves to undefined, so the SDK was silently receiving
no region at all. Cache priming on Contentstack Launch deployments was
broken for every region except exact uppercase EU.

The app itself was unaffected at runtime since lib/contentstack.ts
already passed the string directly.

Fix

Drop the enum lookup, pass the env var string directly — the same
approach used everywhere else in the codebase. Also removed the now
unused Region import.

[github-actions]

🔒 Security Scan Results

ℹ️ Note: Only vulnerabilities with available fixes (upgrades or patches) are counted toward thresholds.

Check Type	Count (with fixes)	Without fixes	Threshold	Result
🔴 Critical Severity	0	0	10	✅ Passed
🟠 High Severity	0	0	25	✅ Passed
🟡 Medium Severity	0	22	500	✅ Passed
🔵 Low Severity	0	0	1000	✅ Passed

⏱️ SLA Breach Summary

✅ No SLA breaches detected. All vulnerabilities are within acceptable time thresholds.

Severity	Breaches (with fixes)	Breaches (no fixes)	SLA Threshold (with/no fixes)	Status
🔴 Critical	0	0	15 / 30 days	✅ Passed
🟠 High	0	0	30 / 120 days	✅ Passed
🟡 Medium	0	0	90 / 365 days	✅ Passed
🔵 Low	0	0	180 / 365 days	✅ Passed

ℹ️ Vulnerabilities Without Available Fixes (Informational Only)

The following vulnerabilities were detected but do not have fixes available (no upgrade or patch). These are excluded from failure thresholds:

• Critical without fixes: 0
• High without fixes: 0
• Medium without fixes: 22
• Low without fixes: 0

✅ BUILD PASSED - All security checks passed