feat: rejection duration after threshold breach

[parmesant]

Fixes #XXXX.

Description

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This PR has:

• been tested to ensure log ingestion and log query works.
• added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
• added documentation for new or modified features or behaviors.

Summary by CodeRabbit

• New Features

  • Added a configurable rejection duration for resource checks.
  • Configure the delay using --rejection-duration or P_REJECTION_DURATION; the default is 30 seconds.

• Behavior Updates

  • Resource checks now wait for the configured duration after utilization exceeds the threshold before checking again.
  • Process metrics continue to be sampled during rejection delays.
  • Shutdown handling remains responsive while a rejection delay is in progress.

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Reviewing files that changed from the base of the PR and between ce8b43d and d2a2074.

📒 Files selected for processing (1)

• src/handlers/http/resource_check.rs

🚧 Files skipped from review as they are similar to previous changes (1)

• src/handlers/http/resource_check.rs

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Walkthrough

The CLI adds a configurable rejection duration with a 30-second default. Resource monitoring shares process-metrics sampling between regular polling and rejection handling. Rejection delays now support continued sampling and shutdown cancellation.

Changes

Resource rejection duration

Layer / File(s)	Summary
Configure and apply rejection duration src/cli.rs, src/handlers/http/resource_check.rs	Options adds validated rejection_duration support through CLI and environment configuration. Resource monitoring uses a shared metrics helper. The rejection loop samples metrics during the delay and exits on shutdown.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: ⚪ Minimal · up to d2a20

The change adds configurable rejection delays with continued resource sampling and shutdown cancellation. No concrete correctness or production-impact issue is evidenced, so it is mergeable with normal checks.

🚥 Pre-merge checks | ✅ 3 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description contains only the unfilled template. It does not explain the goal, solution, rationale, key changes, testing, comments, or documentation status.	Add a completed Description section with the goal, chosen solution and rationale, and key changes. Replace or remove the placeholder issue reference. Mark the checklist items accurately and provide testing and documentation details.
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 2 functions across 2 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly describes the main change: adding rejection duration behavior after a threshold breach.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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Actionable comments posted: 1

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Inline comments:
In `@src/handlers/http/resource_check.rs`:
- Line 85: Update the resource-check rejection-delay branch around the
tokio::time::sleep call so the delay is cancellable by shutdown and does not
block the outer select! from polling process_metrics_interval. Preserve the
existing rejection duration while concurrently handling shutdown_rx and
process-metrics updates during the delay.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Essentials

Run ID: 2bdf23ba-028d-4145-936e-43ee285fe296

📥 Commits

Reviewing files that changed from the base of the PR and between 91183b6 and ce8b43d.

📒 Files selected for processing (2)

• src/cli.rs
• src/handlers/http/resource_check.rs

Included review availability: Your plan provides up to 8 included reviews per hour; 7 remain after this review.