Move all pure parse/discover helpers (message extraction, project-path, codex
helpers, discovery) out of db.mjs/indexer.mjs into scripts/parsing.mjs, which
imports only node:fs/path/os. Providers now import from parsing.mjs, so the
provider import graph no longer transitively loads node:sqlite — a prerequisite
for the app (Electron/Node without node:sqlite) to consume the compiled core.
Verbatim move, no behavior change; indexer.mjs 840→209 lines. 119/119.
