feat(utils): add performance observer

[BioPhoton]

This PR implements:

• performance observer util
• type helper for data flow

Types are used in followup PR #1210

[nx-cloud]

View your CI Pipeline Execution ↗ for commit 12be09c

Command	Status	Duration	Result
nx run-many -t unit-test,int-test	✅ Succeeded	1m 57s	View ↗

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☁️ Nx Cloud last updated this comment at 2026-01-10 00:43:19 UTC

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commit: 12be09c

[github-actions]

Code PushUp

🤨 Code PushUp report has both improvements and regressions – compared current commit 6712550 with previous commit 4d69dc3.

🕵️ See full comparison in Code PushUp portal 🔍

🏷️ Categories

🏷️ Category	⭐ Previous score	⭐ Current score	🔄 Score change
Documentation	🔴 36	🔴 34
Performance	🔴 36	🔴 37
Code coverage	🟢 91	🟢 91
Bug prevention	🟡 75	🟡 75
Axe Accessibility	🟡 88	🟡 88
Code style	🟢 99	🟢 99	–
Security	🟡 51	🟡 51	–
Updates	🟡 78	🟡 78	–
Type Safety	🟡 67	🟡 67	–
Miscellaneous	🟡 67	🟡 67	–
Accessibility	🟢 92	🟢 92	–
Best Practices	🟢 100	🟢 100	–
SEO	🟢 92	🟢 92	–

👍 1 group improved, 👎 2 groups regressed, 👍 5 audits improved, 👎 6 audits regressed, 15 audits changed without impacting score

🗃️ Groups

🔌 Plugin	🗃️ Group	⭐ Previous score	⭐ Current score	🔄 Score change
JSDocs coverage	Documentation coverage	🔴 36	🔴 34
Lighthouse	Performance	🔴 36	🔴 37
Code coverage	Code coverage metrics	🟢 91	🟢 91

31 other groups are unchanged.

🛡️ Audits

🔌 Plugin	🛡️ Audit	📏 Previous value	📏 Current value	🔄 Value change
Lighthouse	Initial server response time was short	🟥 Root document took 630 ms	🟩 Root document took 520 ms
JSDocs coverage	Methods coverage	🟨 8 undocumented methods	🟥 13 undocumented methods
Lighthouse	Speed Index	🟥 6.7 s	🟥 6.1 s
JSDocs coverage	Types coverage	🟥 248 undocumented types	🟥 260 undocumented types
JSDocs coverage	Classes coverage	🟥 6 undocumented classes	🟥 7 undocumented classes
Lighthouse	Time to Interactive	🟥 13.4 s	🟥 13.1 s
Code coverage	Line coverage	🟨 87 %	🟨 86.2 %
Code coverage	Function coverage	🟩 94 %	🟩 93.4 %
JSDocs coverage	Functions coverage	🟥 587 undocumented functions	🟥 597 undocumented functions
JSDocs coverage	Variables coverage	🟥 268 undocumented variables	🟥 271 undocumented variables
Code coverage	Branch coverage	🟨 87.3 %	🟨 87.3 %
Lighthouse	Avoids enormous network payloads	🟩 Total size was 2,106 KiB	🟩 Total size was 2,119 KiB
Lighthouse	Server Backend Latencies	🟩 260 ms	🟩 1,260 ms
Lighthouse	Uses efficient cache policy on static assets	🟨 31 resources found	🟨 31 resources found
Lighthouse	Remove duplicate modules in JavaScript bundles	🟥 Potential savings of 107 KiB	🟥 Potential savings of 104 KiB
Lighthouse	Metrics	🟩 100%	🟩 100%
Lighthouse	Minimizes main-thread work	🟥 9.3 s	🟥 9.0 s
Lighthouse	Reduce unused JavaScript	🟥 Potential savings of 221 KiB	🟥 Potential savings of 222 KiB
Lighthouse	Reduce unused CSS	🟥 Potential savings of 95 KiB	🟥 Potential savings of 95 KiB
Lighthouse	Largest Contentful Paint	🟥 11.5 s	🟥 11.6 s
Lighthouse	Max Potential First Input Delay	🟥 1,090 ms	🟥 970 ms
Lighthouse	JavaScript execution time	🟥 4.4 s	🟥 4.3 s
Lighthouse	Total Blocking Time	🟥 1,780 ms	🟥 1,750 ms
Lighthouse	First Contentful Paint	🟥 3.1 s	🟥 3.1 s
JSDocs coverage	Properties coverage	🟥 16 undocumented properties	🟥 24 undocumented properties
Lighthouse	Network Round Trip Times	🟩 20 ms	🟩 20 ms

653 other audits are unchanged.

[github-actions]

Code PushUp

🤨 Code PushUp report has both improvements and regressions – compared current commit 6712550 with previous commit 4d69dc3.

💼 Project utils

🤨 Code PushUp report has both improvements and regressions.

🕵️ See full comparison in Code PushUp portal 🔍

🏷️ Category	⭐ Previous score	⭐ Current score	🔄 Score change
Documentation	🔴 38	🔴 36
Code coverage	🟢 95	🟢 94

4 other categories are unchanged.

👎 2 groups regressed, 👍 2 audits improved, 👎 6 audits regressed, 1 audit changed without impacting score

🗃️ Groups

🔌 Plugin	🗃️ Group	⭐ Previous score	⭐ Current score	🔄 Score change
JSDocs coverage	Documentation coverage	🔴 38	🔴 36
Code coverage	Code coverage metrics	🟢 95	🟢 94

13 other groups are unchanged.

🛡️ Audits

🔌 Plugin	🛡️ Audit	📏 Previous value	📏 Current value	🔄 Value change
JSDocs coverage	Types coverage	🟥 47 undocumented types	🟥 59 undocumented types
JSDocs coverage	Methods coverage	🟨 8 undocumented methods	🟥 13 undocumented methods
JSDocs coverage	Classes coverage	🟥 3 undocumented classes	🟥 4 undocumented classes
Code coverage	Line coverage	🟩 97 %	🟩 93.8 %
JSDocs coverage	Functions coverage	🟥 236 undocumented functions	🟥 246 undocumented functions
Code coverage	Function coverage	🟩 95.6 %	🟩 95.8 %
JSDocs coverage	Variables coverage	🟥 40 undocumented variables	🟥 43 undocumented variables
Code coverage	Branch coverage	🟩 91.9 %	🟩 91.8 %
JSDocs coverage	Properties coverage	🟥 16 undocumented properties	🟥 24 undocumented properties

435 other audits are unchanged.

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13 other projects are unchanged.