refactor: compile the crate once — main.rs uses the library

main.rs re-declared nearly every module (`mod ai; mod database; …`)
that lib.rs also declared, so the ~100k-line crate compiled twice in
every build (lib for the src/bin tools, bin for the server) and the
test suite ran most tests twice. watcher.rs even reached into the lib
copy via `image_api::` from inside the bin copy.

The six bin-only modules (backfill, handlers, hls_stats, knowledge,
reels, watcher) move into lib.rs; main.rs keeps only startup wiring
over `use image_api::…`. A few items main calls become `pub`, and the
dead_code allowances that only existed because each copy saw half the
callers are gone. CLAUDE.md says not to reintroduce `mod` in main.rs.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/main.rs

@@ -1,9 +1,7 @@
+//! The server binary. Everything it runs lives in the `image_api`
+//! library so the crate compiles once, shared with the `src/bin` tools.
 #![allow(clippy::too_many_arguments)]
 
-#[macro_use]
-extern crate diesel;
-extern crate rayon;
-
 use actix_web::web::Data;
 use actix_web_prom::PrometheusMetricsBuilder;
 use diesel_migrations::{EmbeddedMigrations, MigrationHarness, embed_migrations};
@@ -18,62 +16,16 @@ use actix_web::{App, HttpResponse, HttpServer, middleware, web};
 use diesel::sqlite::Sqlite;
 use std::error::Error;
 
-use crate::ai::InsightGenerator;
-use crate::auth::login;
-use crate::data::*;
-use crate::database::*;
-use crate::files::{RealFileSystem, move_file};
-use crate::service::ServiceBuilder;
-use crate::state::AppState;
-use crate::tags::*;
+use image_api::ai::InsightGenerator;
+use image_api::auth::login;
+use image_api::database::*;
+use image_api::files::{RealFileSystem, move_file};
+use image_api::service::ServiceBuilder;
+use image_api::state::AppState;
+use image_api::tags::*;
+use image_api::*;
 use log::{error, info};
 
-mod ai;
-mod auth;
-mod backfill;
-// Display-zone helpers land in the read-side cutover (#119/#120); the
-// binary's private copy of this module doesn't use them yet.
-#[allow(dead_code)]
-mod camera_tz;
-mod clip_search;
-mod clip_watch;
-mod content_hash;
-mod data;
-mod database;
-mod date_resolver;
-mod date_view;
-mod duplicates;
-mod error;
-mod exif;
-mod face_watch;
-mod faces;
-mod file_scan;
-mod file_types;
-mod files;
-mod geo;
-mod handlers;
-mod hls_stats;
-mod libraries;
-mod library_maintenance;
-mod perceptual_hash;
-mod state;
-mod tags;
-mod thumbnails;
-mod unified_search;
-mod utils;
-mod video;
-mod watcher;
-
-mod knowledge;
-mod memories;
-mod otel;
-mod personas;
-mod prefs;
-mod reels;
-mod service;
-#[cfg(test)]
-mod testhelpers;
-
 pub const MIGRATIONS: EmbeddedMigrations = embed_migrations!();
 
 fn main() -> std::io::Result<()> {
@@ -85,7 +37,7 @@ fn main() -> std::io::Result<()> {
 
     // Recover orphaned insight generation jobs from a previous crash.
     {
-        use crate::database::{InsightGenerationJobDao, SqliteInsightGenerationJobDao};
+        use image_api::database::{InsightGenerationJobDao, SqliteInsightGenerationJobDao};
         let mut dao = SqliteInsightGenerationJobDao::new();
         match dao.recover_orphaned_jobs() {
             Ok(n) if n > 0 => {
@@ -228,9 +180,9 @@ fn main() -> std::io::Result<()> {
 
         // Spawn background job to generate daily conversation summaries
         {
-            use crate::ai::generate_daily_summaries;
-            use crate::database::{DailySummaryDao, SqliteDailySummaryDao};
             use chrono::NaiveDate;
+            use image_api::ai::generate_daily_summaries;
+            use image_api::database::{DailySummaryDao, SqliteDailySummaryDao};
 
             // Configure date range for summary generation
             // Default: August 2024 ±30 days (July 1 - September 30, 2024)
@@ -453,7 +405,7 @@ fn main() -> std::io::Result<()> {
                     Box::new(database::SqlitePersonaDao::new()),
                 )))
                 .app_data::<Data<Mutex<faces::SqliteFaceDao>>>(Data::new(Mutex::new(face_dao)))
-                .app_data::<Data<crate::ai::face_client::FaceClient>>(Data::new(
+                .app_data::<Data<image_api::ai::face_client::FaceClient>>(Data::new(
                     app_data.face_client.clone(),
                 ))
                 .app_data(mp::form::MultipartFormConfig::default().total_limit(1024 * 1024 * 1024)) // 1GB upload limit