Fix podcast support critical bugs from code review

- Fix boolean scanning from SQLite INTEGER columns (intToBool helper)
- Fix BrowseSet LIMIT 0 returning zero episodes (use 1000 instead)
- Fix checkFeed double-fetch by parsing from resp.Body directly
  + Add ParseFeedReader for body reuse
- Fix file handle leak in DownloadEpisode (explicit Close before ImportMediaFile)
- Fix incomplete rollback in DownloadEpisode (remove file + delete media row)
- Fix 204 No Content handler writing 'null' body
- Fix DownloadCoverImage to accept *http.Client with timeout
- Deduplicate uniqueFilename into shared internal/service/filename.go
- Wire frontend renderPodcastEpisodes into renderBrowse from API data
- Refactor podcasts.js: remove extra API call, fix toggle toast, remove duplicate toast
- Add Config.PodcastCheckMinutes + PODCAST_CHECK_INTERVAL_MINUTES env var
- Start background CheckFeeds goroutine in main.go with ticker
- Update NewPodcastService to accept checkInterval parameter
- Log errors from CheckFeeds and episode creation instead of silently discarding

1 files changed, 31 insertions, 0 deletions

diff --git a/internal/service/filename.go b/internal/service/filename.go
new file mode 100644
index 0000000..9303de6
--- /dev/null
+++ b/internal/service/filename.go
@@ -0,0 +1,31 @@
+package service
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// uniqueFilename returns a non-conflicting full path by appending (n)
+// if a file with the same name already exists in dir.
+func uniqueFilename(dir, filename string) string {
+	filename = filepath.Base(filename)
+	if filename == "." || filename == ".." || filename == "" {
+		return ""
+	}
+	ext := filepath.Ext(filename)
+	base := strings.TrimSuffix(filename, ext)
+
+	candidate := filepath.Join(dir, filename)
+	if _, err := os.Stat(candidate); os.IsNotExist(err) {
+		return candidate
+	}
+
+	for i := 1; ; i++ {
+		candidate = filepath.Join(dir, fmt.Sprintf("%s(%d)%s", base, i, ext))
+		if _, err := os.Stat(candidate); os.IsNotExist(err) {
+			return candidate
+		}
+	}
+}