fix(knowledge): keep a bundle's document token totals on import - #9495

Summary

• Imported documents now keep the token total the source document had. The import was summing the embedding tokenizer's per-chunk counts, which estimate differently from the chunker that produced the source total, so totals came out about 15% high. The manifest already carries the source total; the prepared index now passes it through.
• Removed the tokenCount ?? sum-of-chunks fallback added in feat(knowledge): import knowledge base bundles through the API and sim knowledge import #9327: both processing branches now always supply a total, so the upload path behaves exactly as it did before feat(knowledge): import knowledge base bundles through the API and sim knowledge import #9327.
• Manifest tokenCount and characterCount are bounded to the integer columns they're written to, so an out-of-range bundle is refused up front instead of failing each document at its final write.
• Log "indexing N chunks with their bundled vectors" instead of "generating embeddings" when vectors come from the bundle (no embedding call is made on that path).

Type of Change

• Bug fix

Testing

• bundle-import.integration.ts (11 tests, real Postgres/Redis): the round-trip tests now assert imported token totals match the source; both fail on the pre-fix service.ts and pass with the fix
• import-archive.test.ts (19 tests): new case refusing an out-of-range count; fails without the bound
• Processing-path integration suites unchanged and passing: upload-read-provenance, embedding-processing-recovery, embedding-insert-batches, stored-document-recovery, processing-lock-scope, dormant-search-processing (71 tests)
• documents/service.test.ts, biome on changed files; type-check and audits in CI

Checklist

• Code follows project style guidelines
• Self-reviewed my changes
• Tests added/updated and passing (new tests pass the test-audit authoring gate)
• No new warnings introduced
• I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)