feat: Phase 1 handover - schema migration, correction mechanism, API fixes

Schema changes: dev.chunks->dev.chunk, remove old_chunk_id/chunk_index
Correction: asr-1.json format, generate/apply scripts
API: 37/37 endpoints fixed and tested
Docs: HANDOVER_V2.0.md for M4

src/playground.rs

@@ -2147,7 +2147,7 @@ async fn main() -> Result<()> {
                 let mut chunk = Chunk::from_seconds(
                     file_id as i32,
                     uuid.clone(),
-                    i as u32,
+                    format!("{}", i),
                     ChunkType::Sentence,
                     ChunkRule::Rule1,
                     seg.start,
@@ -2193,7 +2193,7 @@ async fn main() -> Result<()> {
                 let chunk = Chunk::from_seconds(
                     file_id as i32,
                     uuid.clone(),
-                    i as u32,
+                    format!("cut_{}", i),
                     ChunkType::Cut,
                     ChunkRule::Rule1,
                     scene.start_time,
@@ -2216,7 +2216,7 @@ async fn main() -> Result<()> {
                 let chunk = Chunk::new(
                     file_id as i32,
                     uuid.clone(),
-                    i as u32,
+                    format!("time_{}", i),
                     ChunkType::TimeBased,
                     ChunkRule::Rule1,
                     tc.start_frame,