fix: bump Angular 21.2.x patch deps to resolve Snyk vulnerabilities

[cs-raj]

Summary

• Bumps all exact-pinned Angular dependencies from 21.2.17 → 21.2.19 and build tooling from 21.2.15 → 21.2.20
• Reduces npm audit vulnerability count from 23 → 11 (12 fixed)
• Build verified passing (ng build) before commit

Packages updated

Package	Before	After
@angular/common	21.2.17	21.2.19
@angular/compiler	21.2.17	21.2.19
@angular/core	21.2.17	21.2.19
@angular/platform-browser	21.2.17	21.2.19
@angular/router	21.2.17	21.2.19
@angular/compiler-cli	21.2.17	21.2.19
@angular-devkit/build-angular	21.2.15	21.2.20
@angular/cli	21.2.15	21.2.20

Remaining 11 vulnerabilities

All remaining issues cascade through nested @angular-devkit/build-angular internals and require npm audit fix --force (breaking changes — outside scope of this PR).

Test plan

• npm install completes cleanly
• npm run build passes with no errors (warnings only — pre-existing CommonJS notices from Contentstack SDK deps)
• Verify npm audit shows 11 remaining (down from 23)

🤖 Generated with Claude Code

[snyk-io]

✅ Snyk checks have passed. No issues have been found so far.

Status	Scan Engine	Critical	High	Medium	Low	Total (0)
✅	Open Source Security	0	0	0	0	0 issues
✅	Licenses	0	0	0	0	0 issues
✅	Code Security	0	0	0	0	0 issues

💻 Catch issues earlier using the plugins for VS Code, JetBrains IDEs, Visual Studio, and Eclipse.

[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	0	0	✅ Passed
🔵 Low Severity	0	0	0	✅ 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

✅ BUILD PASSED - All security checks passed