Move input state tracking to the db to avoid node wide fetch on improved inputs page

[kodjo-anipah]

Description

/nocl
part of #25358

Previously, all input state consumers relied on GET /cluster/inputstates, which performs HTTP fan-out to every cluster node and returns full InputStateSummary objects (config, creator, static fields, etc.).

This approach is:

• Expensive
• Fragile in larger clusters
• Prone to node overload and timeouts

This PR is part of an incremental migration to DB-backed input state endpoints, now that input states are persisted in MongoDB (input_runtime_states collection).

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What this PR adds

Backend

• GET /system/inputstates/summary

  • Lightweight endpoint on InputStatesResource
  • Reads directly from MongoDB
  • No fan-out
  • Returns simplified structure:

    { "inputId": ["RUNNING", "FAILED"] }

• Remove previously made improvements to the InputRegistry and have InputRuntimeStatusProvider use new DB approach.

Frontend

• useInputStateSummary hook

  • Polls every 5s (previously 2s)
  • Pre-computes hasProblematicInputs boolean

• InputsDotBadge

  • Now uses useInputStateSummary
  • Removes dependency on heavy fan-out endpoint for nav badge

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[laura-b-g]

Frontend Quick Review (Scoped)

Focus: Frontend changes only (4 files, ~80 lines of frontend diff)
Reviewer scope: useInputStateSummary.ts (new), InputsDotBadge.tsx, InputsDotBadge.test.tsx, ApiRoutes.ts

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Summary

Replaces the heavy useInputsStates hook (which calls GET /cluster/inputstates — full HTTP fan-out) with a new lightweight useInputStateSummary hook (calls GET /system/inputstates/summary — single MongoDB read) in the InputsDotBadge nav component. Polling interval relaxed from 2s → 5s.

The old useInputsStates hook is not removed — it's still used by 10+ other files (InputsOverview, InputStateBadge, InputStateControl, InputsNotifications, etc.). This PR only migrates InputsDotBadge, which only needs a boolean "are any inputs problematic?" signal.

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Findings

No Issues Found

Area	Assessment
Hook API design	Clean — returns { hasProblematicInputs: boolean; isLoading: boolean }. Minimal surface, single purpose.
Response type alignment	Backend returns Map<String, Set<String>>, serializes to { [inputId]: string[] } — matches the StateSummary type.
Polling interval (5s)	Appropriate for a nav badge indicator. Lighter load than the previous 2s full fan-out.
Error handling	Uses defaultOnError wrapper consistently with other hooks. retry: false is fine since polling retries naturally.
No keepPreviousData needed	Static query key means react-query preserves data between refetches by default. No flash risk.
PROBLEMATIC_STATES set	FAILED, FAILING, SETUP — matches the old inline check in InputsDotBadge. No behavioral change.
Component simplification	InputsDotBadge went from inline state traversal to a simple boolean read. Cleaner.
Tests	Good coverage of all component states: loading, clean, problematic, external issues, combined.

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Issue Coverage

Linked issue: #25358 — "Improve fragile input state fetching"

Issue goal	PR coverage
Add lightweight input state summary endpoint	Backend adds GET /system/inputstates/summary
Move consumers to DB-backed endpoints	Frontend: InputsDotBadge migrated (this scope)
Remove InputRegistry workaround logic	Backend: InputStateCache removed
Decouple input definitions from state	Frontend: new hook fetches states independently

Frontend portion addresses the nav badge consumer. Other frontend consumers (InputsOverview, etc.) remain on the old hook — expected for an incremental migration.

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🤖 AI-generated review (frontend scope only) — verify findings before acting on them.

[laura-b-g]

Frontend-wise the code looks good. I did not test it though, because my setup is messed up. Still working on that.

[xd4rker]

Backend LGTM.
Tested locally, works as expected.