Unify sequence-container maintenance

[ezrosent]

Summary

• Introduce an arity-agnostic MaintenanceTable interface shared by relations and sequence-backed containers.
• Allocate relations and migrated containers from one TableId namespace and schedule them through the same dependency graph, buffers, notifications, merge loop, and rebuild traversal.
• Keep only unmigrated legacy containers in the compatibility rebuild pass.
• Share union-find rebuild state and dirty-container closure across both paths during the transition.

Stack

Draft, stacked on #977. This is PR 5 of 12 in the sequence-backed container stack.

Validation

Validated on the complete 12-commit stack:

• cargo nextest run --workspace: 1,362 tests passed
• cargo test --workspace --doc
• cargo clippy --workspace --all-targets -- -D warnings
• cargo fmt --all -- --check

[codecov-commenter]

Codecov Report

❌ Patch coverage is 95.61905% with 23 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (codex/inline-containers-04-infrastructure@9ee921c). Learn more about missing BASE report.

Files with missing lines	Patch %	Lines
core-relations/src/containers/mod.rs	86.56%	9 Missing ⚠️
core-relations/src/table/sequence.rs	0.00%	9 Missing ⚠️
core-relations/src/containers/sequence.rs	96.62%	3 Missing ⚠️
core-relations/src/free_join/mod.rs	99.35%	2 Missing ⚠️

Additional details and impacted files

@@                             Coverage Diff                              @@
##             codex/inline-containers-04-infrastructure     #978   +/-   ##
============================================================================
  Coverage                                             ?   87.60%           
============================================================================
  Files                                                ?       98           
  Lines                                                ?    37673           
  Branches                                             ?        0           
============================================================================
  Hits                                                 ?    33002           
  Misses                                               ?     4671           
  Partials                                             ?        0           

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[codspeed-hq]

Merging this PR will degrade performance by 2%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 6 improved benchmarks
❌ 6 regressed benchmarks
✅ 25 untouched benchmarks
⏩ 227 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	tests[python_array_optimize]	1.1 s	1.3 s	-14.46%
❌	Simulation	tests[eggcc-extraction]	1.4 s	1.6 s	-14.02%
❌	Simulation	tests[typeinfer]	114.9 ms	129.5 ms	-11.32%
❌	Simulation	tests[eggcc-2mm]	7.7 s	8.5 s	-9.46%
❌	Simulation	tests[luminal-llama]	504.4 ms	554.5 ms	-9.04%
❌	Simulation	tests[repro-665-set-union]	602 ms	635.3 ms	-5.25%
⚡	Simulation	rust_rule_insert_loop[ops1000_funcs0]	632.8 µs	583.5 µs	+8.46%
⚡	Simulation	rust_rule_insert_loop[ops1000_funcs2000]	912.3 µs	844.8 µs	+8%
⚡	Simulation	rust_rule_insert_loop[ops1000_funcs200]	671.1 µs	623.1 µs	+7.7%
⚡	Simulation	rust_rule_insert_loop[ops100000_funcs2000]	50 ms	46.5 ms	+7.68%
⚡	Simulation	rust_rule_insert_loop[ops100000_funcs200]	50.3 ms	47.2 ms	+6.51%
⚡	Simulation	rust_rule_insert_loop[ops100000_funcs0]	50.3 ms	47.2 ms	+6.5%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

---

_{Comparing codex/inline-containers-05-unified-maintenance (14d3f72) with main (716c320)²}

Footnotes

1. 227 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

2. No successful run was found on codex/inline-containers-04-infrastructure (9ee921c) during the generation of this report, so main (716c320) was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩