fix: correct video integration after comic generation

PromptForGalleryVideos now returns []string paths (from recursive walk)
instead of []int page numbers, so GenerateSelectedVideos always has the
exact path to each gallery PNG regardless of which comics/<slug>/
subdirectory it lives in.

Previously, GenerateSelectedVideos passed "." as galleryPath and called
loadGalleryImage with a non-recursive filepath.Glob that could not find
PNGs in subdirectories, causing video generation to always fail with
"no gallery image found".

Additional changes:
- Add VeoGenerator.GenerateVideoFromPath that accepts a full image path
  and writes the MP4 next to the source PNG
- Make runStoryVideos non-fatal: video errors print a warning and return
  nil so comic/PDF/narration outputs are never invalidated by Veo errors
- Add filterPathsByPages helper and tests for the new behaviour
- Add TestFindGalleryPages_Recursive to cover the comics/<slug>/ layout

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 11 insertions, 11 deletions

diff --git a/internal/cli/video_runner.go b/internal/cli/video_runner.go
index 2679a26..96cd7cd 100644
--- a/internal/cli/video_runner.go
+++ b/internal/cli/video_runner.go
@@ -12,15 +12,15 @@ import (
 // (Veo generation is slow and API quotas make parallelism impractical).
 //
 // apiKey is the Google/Gemini API key passed by the caller.
-// selected is the list of gallery page numbers to process (from PromptForGalleryVideos).
-// outputDir is both the directory that contains the gallery PNGs and the
-// destination for the resulting MP4 files (written next to the PNGs).
+// selectedPaths contains the absolute (or relative) paths of the gallery PNGs
+// to animate — typically returned by PromptForGalleryVideos.
 //
 // Each page prints a "Generating…" line before the API call and a "Video saved:"
-// line with the output path on success. The function stops and returns on the
-// first error so callers can log it without silently skipping pages.
-func GenerateSelectedVideos(apiKey string, selected []int, outputDir string) error {
-	if len(selected) == 0 {
+// line with the output path on success. The MP4 is written next to its source
+// PNG so that gallery images and their videos stay in the same directory.
+// The function stops and returns on the first error so the caller can log it.
+func GenerateSelectedVideos(apiKey string, selectedPaths []string) error {
+	if len(selectedPaths) == 0 {
 		return nil
 	}
 
@@ -31,12 +31,12 @@ func GenerateSelectedVideos(apiKey string, selected []int, outputDir string) err
 
 	ctx := context.Background()
 
-	for _, pageNum := range selected {
-		fmt.Printf("Generating video for gallery page %d...\n", pageNum)
+	for _, imgPath := range selectedPaths {
+		fmt.Printf("Generating video for: %s\n", imgPath)
 
-		mp4Path, err := gen.GenerateVideoFromGallery(ctx, outputDir, outputDir, pageNum)
+		mp4Path, err := gen.GenerateVideoFromPath(ctx, imgPath)
 		if err != nil {
-			return fmt.Errorf("cli: generating video for page %d: %w", pageNum, err)
+			return fmt.Errorf("cli: generating video for %s: %w", imgPath, err)
 		}
 
 		fmt.Printf("Video saved: %s\n", mp4Path)