feat(db): add sequences and sequence_clips tables

services/mam-api/src/db/schema_patch_editor.sql

@@ -0,0 +1,35 @@
+-- services/mam-api/src/db/schema_patch_editor.sql
+-- Run once against the Wild Dragon PostgreSQL database.
+
+-- Named timelines within a project (multiple per project, like Premiere)
+CREATE TABLE IF NOT EXISTS sequences (
+  id          UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
+  project_id  UUID NOT NULL REFERENCES projects ON DELETE CASCADE,
+  name        TEXT NOT NULL DEFAULT 'Sequence 1',
+  frame_rate  NUMERIC(6,3) NOT NULL DEFAULT 59.94,
+  width       INTEGER NOT NULL DEFAULT 1920,
+  height      INTEGER NOT NULL DEFAULT 1080,
+  created_at  TIMESTAMPTZ DEFAULT NOW(),
+  updated_at  TIMESTAMPTZ DEFAULT NOW()
+);
+
+CREATE INDEX IF NOT EXISTS idx_sequences_project_id ON sequences(project_id);
+CREATE INDEX IF NOT EXISTS idx_sequences_updated_at ON sequences(updated_at DESC);
+
+-- Clips placed on a sequence timeline
+CREATE TABLE IF NOT EXISTS sequence_clips (
+  id                   UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
+  sequence_id          UUID NOT NULL REFERENCES sequences ON DELETE CASCADE,
+  asset_id             UUID NOT NULL REFERENCES assets ON DELETE CASCADE,
+  track                INTEGER NOT NULL DEFAULT 0,
+  -- track encoding: 0=V1, 1=V2, 100=A1, 101=A2
+  timeline_in_frames   BIGINT NOT NULL,
+  timeline_out_frames  BIGINT NOT NULL,
+  source_in_frames     BIGINT NOT NULL DEFAULT 0,
+  source_out_frames    BIGINT NOT NULL,
+  created_at           TIMESTAMPTZ DEFAULT NOW(),
+  updated_at           TIMESTAMPTZ DEFAULT NOW()
+);
+
+CREATE INDEX IF NOT EXISTS idx_sequence_clips_sequence_id ON sequence_clips(sequence_id);
+CREATE INDEX IF NOT EXISTS idx_sequence_clips_track_position ON sequence_clips(sequence_id, track, timeline_in_frames);