let source_path = top_level_source_path(file_info);

let count = self.processed.entry(source_path.clone()).or_insert(0);

*count += 1;

}

- **enrichment.rs** -- `ReadPool` (lock-free thread-local read connections for enrichment and verification), `enrich_entries_with_index()` (called when entries are stored in the listing cache — streaming, watcher update, re-sort — NOT on `get_file_range`; index freshness is handled by `index-dir-updated` → `refreshIndexSizes` → `getDirStatsBatch`). Integer-keyed fast path: resolve parent dir once → batch-fetch child dir stats by ID → match by name. Falls back to individual path resolution for edge cases.

- **event_loop.rs** -- `run_live_event_loop` (real-time FSEvents/inotify processing after scan completes), `run_replay_event_loop` (cold-start journal replay with two-phase approach), `run_background_verification` (post-replay bidirectional readdir diff), `merge_fs_events` (deduplication with flag priority), `process_live_batch`. All bounded-buffer constants live here.

- **events.rs** -- Tauri event payload structs (`IndexScanStartedEvent`, `IndexScanProgressEvent`, `IndexScanCompleteEvent`, `IndexDirUpdatedEvent`, `IndexReplayProgressEvent`, `IndexReplayCompleteEvent`), `RescanReason` enum, `emit_rescan_notification()`, IPC response types (`IndexStatusResponse`, `IndexDebugStatusResponse`). Also: `ActivityPhase` enum (Replaying/Scanning/Aggregating/Reconciling/Live/Idle) and `PhaseRecord` for the phase timeline system tracked in `DebugStats`.

- **memory_watchdog.rs** -- Background task monitoring resident memory via `mach_task_info` (macOS). Warns at 8 GB, stops indexing at 16 GB, emits `index-memory-warning` event to frontend. No-op stub on non-macOS. Started from `start_indexing()`.

- **writer.rs** -- Single writer thread, owns the write connection, processes `WriteMessage` channel (bounded `sync_channel`, 20K capacity, backpressure via blocking). `WRITER_GENERATION: AtomicU64` (initialized to 1) bumped on every mutation (`InsertEntriesV2`, `UpsertEntryV2`, `DeleteEntryById`, `DeleteSubtreeById`, `TruncateData`) for search index staleness detection. Priority: `UpdateDirStats` before `InsertEntries`. `Flush` variant + async `flush()` method let callers wait for all prior writes to commit. Has both integer-keyed variants (`InsertEntriesV2`, `UpsertEntryV2`, `DeleteEntryById`, `DeleteSubtreeById`, `PropagateDeltaById`) and path-keyed backward-compat variants. The integer-keyed delete/subtree-delete handlers auto-propagate negative deltas via the `parent_id` chain (same pattern as the path-keyed variants). `propagate_delta_by_id` walks the parent chain using `get_parent_id` lookups. `UpsertEntryV2` initializes a zero-valued `dir_stats` row when inserting a NEW directory, so enrichment always has a row (subsequent `PropagateDeltaById` calls update it incrementally). Maintains `AccumulatorMaps` during `InsertEntriesV2` processing (two HashMaps: direct children stats and child dir relationships + an `entries_inserted` counter), cleared on `TruncateData`. On `ComputeAllAggregates`, passes accumulated maps to `aggregator::compute_all_aggregates_with_maps()` to skip expensive full-table-scan SQL queries. Accepts an optional `AppHandle` at spawn time to emit `index-aggregation-progress` events during aggregation (phase, current, total). Also emits `saving_entries` phase progress during `InsertEntriesV2` processing when the expected total is set via `set_expected_total_entries()` (an `Arc<AtomicU64>` shared between the writer thread and the `IndexWriter` handle). No index drop/recreate dance — the composite indexes (`idx_parent_name_folded` on macOS, `idx_parent_name` on Linux) use binary collation and stay present during scans.

- **scanner.rs** -- jwalk-based parallel directory walker. `scan_volume()` for full scan, `scan_subtree()` for targeted subtree rescans (used by post-replay background verification). Uses `ScanContext` (from store.rs) to assign integer IDs and parent IDs during the walk: maintains a `HashMap<PathBuf, i64>` mapping directory paths to assigned IDs. The scan root is mapped to `ROOT_ID` (1). Sends `InsertEntriesV2(Vec<EntryRow>)` batches to the writer. Platform-specific exclusion filters via `should_exclude` (`pub(super)`) — the single exclusion gate for all code paths (scanner, reconciler, event_loop verification, per-navigation verifier). `default_exclusions()` is `#[cfg(test)]` only. Physical sizes (`st_blocks * 512`).

Reads happen on separate WAL connections (any thread). A `ReadPool` provides thread-local read connections for enrichment and verification without contending on the `INDEXING` state-machine mutex.

One DB per volume. **Dev and prod use separate directories** (see AGENTS.md § Debugging):

- **Prod**: `~/Library/Application Support/com.veszelovszki.cmdr/index-{volume_id}.db`

- **Dev**: `~/Library/Application Support/com.veszelovszki.cmdr-dev/index-{volume_id}.db`

Three tables:

- **macOS**: has a `name_folded TEXT NOT NULL` column storing `normalize_for_comparison(name)` (NFD + case fold). Index: `idx_parent_name_folded ON entries (parent_id, name_folded)`.

- **Linux/Windows**: no `name_folded` column. Index: `idx_parent_name ON entries (parent_id, name)`.

- The old `idx_parent(parent_id)` from v5 is removed; the composite indexes replace it.

- `meta` (key TEXT PK, value TEXT) WITHOUT ROWID

WAL mode, 16 MB page cache, `auto_vacuum = INCREMENTAL` (free pages reclaimed via `PRAGMA incremental_vacuum` after truncation). Custom `platform_case` collation registered on every connection: case-insensitive + NFD normalization on macOS, binary on Linux. **Opening the DB with the sqlite3 CLI will fail** on queries touching the name column (the collation isn't registered).

- **Schema v4**: Bumped from v3 to enable `auto_vacuum = INCREMENTAL` (requires DB rebuild since the pragma must be set before table creation).

- **Schema v5**: Replaced composite `UNIQUE INDEX idx_parent_name(parent_id, name)` with simple `INDEX idx_parent(parent_id)`. The composite index with `platform_case` collation was extremely slow to build (~25 min for 5.1M entries). A simple integer index needs no drop/recreate dance during scans.

- **Schema v6**: Added `name_folded` column (macOS only) storing pre-computed `normalize_for_comparison(name)`. Replaced `idx_parent` with platform-conditional composite indexes: `idx_parent_name_folded(parent_id, name_folded)` on macOS, `idx_parent_name(parent_id, name)` on Linux/Windows. `resolve_component` now queries the index directly instead of fetching all children and matching in Rust.

**IPC boundary stays path-based**: Frontend sends filesystem paths, backend resolves path→ID internally via `store::resolve_path()`. No frontend changes needed. IPC dir stats queries (`get_dir_stats`, `get_dir_stats_batch`) use `ReadPool` for lock-free reads, same as enrichment.

**MustScanSubDirs uses reconciliation, not delete-then-reinsert**: `reconcile_subtree()` diffs the filesystem against the DB directory-by-directory, only inserting/deleting/updating entries that changed. This is safe to interrupt at any point (no bulk delete phase that could leave the DB empty). For brand-new directories discovered during reconciliation, a `flush_blocking()` + re-resolve cycle ensures their IDs are available before recursing into them. `scanner::scan_subtree` (which uses destructive `DeleteDescendantsById`) is used by post-replay background verification for newly discovered directories.