buildIndex's claude branch now parses via providers/claude.ts and writes via
persist.ts instead of the inlined indexJsonl. Behavior is equivalent — the full
buildIndex integration suite (runtime.test.mjs) stays green, 116/116 — and a
force rebuild of the real ~/.obelisk index (327 sessions, 119k messages)
reproduced identical session counts with project_path fully populated.
codex, indexSubagentMeta, workflows, history and the project_path pass are
untouched. indexJsonl is now unused by buildIndex (kept for its drift test;
removed once codex is migrated).
Adds tests/incremental-index.test.mjs: verifies resume/accumulate through the
full buildIndex path (append new lines to an indexed session → incremental
build resumes from the cursor, message_count accumulates, no duplicates). The
30s shouldSkipBuild debounce is cleared in-test so the incremental run fires.
