feat(config): allow tuning pool pings, checkout retries and connection recycling

[yordis]

• Users could not cap idle pings, retry checkouts after a disconnect, or recycle aged connections because the config allowlist dropped those DBConnection options without warning.
• Only the main pool may recycle connections, because every other connection carries state that dies with it (subscription and migration advisory locks, LISTEN registrations).

[cursor]

PR Summary

Low Risk
Config allowlist and targeted stripping of max_lifetime on session pools; behavior change is opt-in via new options with guards for stateful connections.

Overview
Exposes DBConnection pool tuning (checkout_retries, idle_limit, max_lifetime) through EventStore config by adding them to the Postgrex option allowlist, so they are no longer silently dropped when users set them.

max_lifetime is only applied to the main write/read pool via postgrex_opts; default_postgrex_opts (used for advisory-lock and notification/LISTEN session connections) strips max_lifetime so those long-lived connections are not recycled and lose advisory locks or LISTEN state. Other new options still flow through to session-mode pools.

Adds an explicit db_connection ~> 2.10 dependency and tests that assert main-pool vs session-pool option behavior.

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[coderabbitai]

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Walkthrough

The Postgrex option filters now retain :checkout_retries and :idle_limit for all three pools. The main pool also retains :max_lifetime; advisory-lock and notification pools exclude it.

Changes

Pool Option Filtering

Layer / File(s)	Summary
Shared Postgrex options lib/event_store/config.ex, test/config_test.exs	The shared option filter retains :checkout_retries and :idle_limit. Tests check that all three pool option builders include both options.
Main-pool lifetime option lib/event_store/config.ex, test/config_test.exs	The main pool retains :max_lifetime, while the advisory-lock and notification pools exclude it. Tests check this distinction.

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

Change: Feature

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% 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 (4 passed)

Check name	Status	Explanation
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.
Title check	✅ Passed	The title clearly summarizes the main configuration changes: pool tuning, checkout retries, and connection recycling.
Description check	✅ Passed	The description accurately explains the newly supported options and why max_lifetime applies only to the main pool.

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_{A rabbit checks the pool options with care
Two shared settings now travel there
The main pool keeps lifetime in view
The other pools leave that option through
Then hops away beneath the moon}

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Actionable comments posted: 1

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Inline comments:
Review comments at @lib/event_store/config.ex:
- Line 168: Add a direct DBConnection dependency constraint in the project
dependency list requiring version 2.10 or later within the compatible 2.x range,
so consumers resolving Postgrex cannot select a version without `:max_lifetime`
support.

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ℹ️ Review info

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Run ID: bf3d57b4-1efe-441d-b7cd-64a114306a94

📥 Commits

Reviewing files that changed from the base of the PR and between 8d0af74 and 91d3242.

📒 Files selected for processing (2)

• lib/event_store/config.ex
• test/config_test.exs

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[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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