fix(sqlite-native): restore native startup kv preload

[NathanFlurry]

Description

Please include a summary of the changes and the related issue. Please also include relevant motivation and context.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

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Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[NathanFlurry]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
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• chore: lockfile lefthook #4647
• fix(rivetkit): surface native sqlite kv errors to callers #4645
• fix(rivetkit): prevent sleep races during disconnect and db work #4644
• fix(rivetkit): isolate engine envoys and propagate startup failures #4643
• test(rivetkit): remove wasm sqlite-only fixtures and coverage #4642
• chore(sqlite-vfs): remove wasm sqlite packages and workspace wiring #4641
• chore(rivetkit): remove wasm sqlite runtime #4614
• fix(sqlite-native): restore native startup kv preload #4639 👈 (View in Graphite)
• fix(sqlite-native): delete metadata before chunk range #4638
• fix(sqlite-native): keep truncate cache coherent #4637
• fix(sqlite-vfs): use delete range for truncate cleanup #4636
• fix(sqlite-native): restore kv error hook #4635
• perf(sqlite-native): avoid cloning cached read chunks #4634
• perf(sqlite-native): gate kv operation labels #4633
• perf(sqlite-native): reuse read cache for partial writes #4632
• perf(sqlite-native): remove delete file existence probe #4631
• fix(sqlite-native): gate native read cache behind env var #4630
• fix(pegboard): isolate runner config dc lookup failures #4625 : 1 other dependent PR (#4626 )
• docs(pegboard): note runner config upsert split write risk #4624
• fix(pegboard): unpack global runner config keys correctly #4623
• fix(pegboard-gateway): enforce tunnel message state #4622
• fix(pegboard-runner): clear terminal tunnel routes #4621
• fix(pegboard): skip protocol version keys in runner pool backfill #4620
• fix(pegboard): create missing normal runner configs #4619
• fix(epoxy): reuse cached optimistic value #4618
• main

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[claude]

PR Review: fix(sqlite-native): restore native startup kv preload

This PR restores the native startup KV preload path by threading preloaded_kv through the bridge, wrapper, and VFS layers. The overall design is sound and well-structured.

Potential issue: startup_preload_put silently drops new keys

vfs.rs -- startup_preload_put only updates keys already present; it does not insert new ones. If SQLite writes a key that was in the preload, then deletes it, then writes it again, the key is not re-added to the cache. Subsequent reads fall through to the network and get the correct value, so there is no correctness bug. But the silent no-op is non-obvious. The test name update_without_growing signals the intent; a one-line comment on the function would make the invariant explicit.

Dead fields in decodePreloadedKv

wrapper.js -- decodePreloadedKv returns { entries, requestedGetKeys, requestedPrefixes }, but only entries is consumed downstream. requestedGetKeys and requestedPrefixes are decoded but appear unused. Either remove them now and restore when needed, or add a comment explaining they are reserved for future use.

Minor: unconditional clone before potentially-failing async call

vfs.rs -- kv_put and kv_delete now do keys.clone() and values.clone() before the block_on call so the clones are available for update_startup_preload afterward. The clone happens even on failure, where the copies are discarded. The preload data is small so this is not a practical concern, but it is a behavioral change from the original code.

Test coverage

The three unit tests for the helper functions are clear and cover the main cases. A higher-level integration test that constructs a VfsContext with preloaded entries and exercises the kv_get hit/miss/merge path would provide additional confidence, but is not strictly required to merge.

Positive notes

• The binary-search-sorted layout for preload lookup is efficient and correct.
• Keeping the preload in sync on put/delete/delete_range is the right design; stale entries cannot cause incorrect reads.
• startup_preload: Mutex<Option<...>> clearly separates no-preload from empty-preload.
• The comment distinguishing the startup preload from the opt-in read cache is clear and valuable.