Add EXIF search infrastructure (Phase 1 & 2)

Implements foundation for EXIF-based photo search capabilities:

- Add geo.rs module with GPS distance calculations (Haversine + bounding box)
- Extend FilesRequest with EXIF search parameters (camera, GPS, date, media type)
- Add MediaType enum and DateTakenAsc/DateTakenDesc sort options
- Create date_taken index migration for efficient date queries
- Implement ExifDao methods: get_exif_batch, query_by_exif, get_camera_makes
- Add FileWithMetadata struct for date-aware sorting
- Implement date sorting with filename extraction fallback
- Make extract_date_from_filename public for reuse

Next: Integrate EXIF filtering into list_photos() and enhance get_all_tags()

src/files.rs

@@ -28,6 +28,14 @@ use crate::video::actors::StreamActor;
 use path_absolutize::*;
 use rand::prelude::SliceRandom;
 use rand::thread_rng;
+
+/// File metadata for sorting and filtering
+/// Includes tag count and optional date for date-based sorting
+pub struct FileWithMetadata {
+    pub file_name: String,
+    pub tag_count: i64,
+    pub date_taken: Option<i64>, // Unix timestamp from EXIF or filename extraction
+}
 use serde::Deserialize;
 
 pub async fn list_photos<TagD: TagDao, FS: FileSystemAccess>(
@@ -264,6 +272,56 @@ fn sort(mut files: Vec<FileWithTagCount>, sort_type: SortType) -> Vec<String> {
         SortType::TagCountDesc => {
             files.sort_by(|l, r| r.tag_count.cmp(&l.tag_count));
         }
+        SortType::DateTakenAsc | SortType::DateTakenDesc => {
+            // Date sorting not yet implemented for FileWithTagCount
+            // Will be implemented when integrating with FileWithMetadata
+            // For now, fall back to name sorting
+            files.sort_by(|l, r| l.file_name.cmp(&r.file_name));
+        }
+    }
+
+    files
+        .iter()
+        .map(|f| f.file_name.clone())
+        .collect::<Vec<String>>()
+}
+
+/// Sort files with metadata support (including date sorting)
+fn sort_with_metadata(mut files: Vec<FileWithMetadata>, sort_type: SortType) -> Vec<String> {
+    match sort_type {
+        SortType::Shuffle => files.shuffle(&mut thread_rng()),
+        SortType::NameAsc => {
+            files.sort_by(|l, r| l.file_name.cmp(&r.file_name));
+        }
+        SortType::NameDesc => {
+            files.sort_by(|l, r| r.file_name.cmp(&l.file_name));
+        }
+        SortType::TagCountAsc => {
+            files.sort_by(|l, r| l.tag_count.cmp(&r.tag_count));
+        }
+        SortType::TagCountDesc => {
+            files.sort_by(|l, r| r.tag_count.cmp(&l.tag_count));
+        }
+        SortType::DateTakenAsc => {
+            files.sort_by(|l, r| {
+                match (l.date_taken, r.date_taken) {
+                    (Some(a), Some(b)) => a.cmp(&b),
+                    (Some(_), None) => std::cmp::Ordering::Less, // Dated photos first
+                    (None, Some(_)) => std::cmp::Ordering::Greater,
+                    (None, None) => l.file_name.cmp(&r.file_name), // Fallback to name
+                }
+            });
+        }
+        SortType::DateTakenDesc => {
+            files.sort_by(|l, r| {
+                match (l.date_taken, r.date_taken) {
+                    (Some(a), Some(b)) => b.cmp(&a), // Reverse for descending
+                    (Some(_), None) => std::cmp::Ordering::Less, // Dated photos first
+                    (None, Some(_)) => std::cmp::Ordering::Greater,
+                    (None, None) => r.file_name.cmp(&l.file_name), // Fallback reversed
+                }
+            });
+        }
     }
 
     files